diff --git a/kmk/extensions/ble_split.py b/kmk/extensions/ble_split.py
index baac766..67c87a4 100644
--- a/kmk/extensions/ble_split.py
+++ b/kmk/extensions/ble_split.py
@@ -1,3 +1,4 @@
+'''Enables splitting keyboards wirelessly'''
 from adafruit_ble import BLERadio
 from adafruit_ble.advertising.standard import ProvideServicesAdvertisement
 from adafruit_ble.services.nordic import UARTService
@@ -8,6 +9,8 @@ from kmk.matrix import intify_coordinate
 
 
 class BLE_Split(Extension):
+    '''Enables splitting keyboards wirelessly'''
+
     def __init__(self, split_flip=True, split_side=None, hid_type=HIDModes.BLE):
         self._is_target = True
         self._uart_buffer = []
@@ -28,7 +31,20 @@ class BLE_Split(Extension):
         return f'BLE_SPLIT({self._to_dict()})'
 
     def _to_dict(self):
-        return f'BLE_Split( _ble={self._ble} _ble_last_scan={self._ble_last_scan} _is_target={self._is_target} _uart_buffer={self._uart_buffer} _split_flip={self.split_flip} _split_side={self.split_side} )'
+        return f'''
+        BLE_Split( _ble={self._ble}
+        _ble_last_scan={self._ble_last_scan}
+        _is_target={self._is_target}
+        _uart_buffer={self._uart_buffer}
+        _split_flip={self.split_flip}
+        _split_side={self.split_side} )
+        '''
+
+    def on_runtime_enable(self, keyboard):
+        return
+
+    def on_runtime_disable(self, keyboard):
+        return
 
     def during_bootup(self, keyboard):
         self._is_target = bool(self.split_side == 'Left')
@@ -49,32 +65,32 @@ class BLE_Split(Extension):
                 for cidx in range(cols_to_calc):
                     keyboard.coord_mapping.append(intify_coordinate(ridx, cidx))
 
-    def before_matrix_scan(self, keyboard_state):
-        self.check_all_connections()
+    def before_matrix_scan(self, keyboard):
+        self._check_all_connections()
         return self._receive()
 
-    def after_matrix_scan(self, keyboard_state, matrix_update):
+    def after_matrix_scan(self, keyboard, matrix_update):
         if matrix_update:
             matrix_update = self._send(matrix_update)
             return matrix_update
+        return None
 
-    def check_all_connections(self):
+    def before_hid_send(self, keyboard):
+        return
+
+    def after_hid_send(self, keyboard):
+        return
+
+    def _check_all_connections(self):
+        '''Validates the correct number of BLE connections'''
         self._connection_count = len(self._ble.connections)
         if self._is_target and self._connection_count < 2:
-            self.target_advertise()
+            self._target_advertise()
         elif not self._is_target and self._connection_count < 1:
-            self.initiator_scan()
+            self._initiator_scan()
 
-    def connect(self):
-        if not self.check_all_connections() and self.ble_rescan_timer:
-            if self.split_side == 'Left':
-                self._is_target = True
-                self.target_advertise()
-            elif self.split_side == 'Right':
-                self._is_target = False
-                self.initiator_scan()
-
-    def initiator_scan(self):
+    def _initiator_scan(self):
+        '''Scans for target device'''
         self._uart = None
         self._uart_connection = None
         # See if any existing connections are providing UARTService.
@@ -83,6 +99,7 @@ class BLE_Split(Extension):
             for connection in self._ble.connections:
                 if UARTService in connection:
                     self._uart_connection = connection
+                    self._uart_connection.connection_interval = 11.25
                     self._uart = self._uart_connection[UARTService]
                     break
 
@@ -93,14 +110,15 @@ class BLE_Split(Extension):
                 print('Scanning')
                 if UARTService in adv.services:
                     self._uart_connection = self._ble.connect(adv)
+                    self._uart_connection.connection_interval = 11.25
                     self._uart = self._uart_connection[UARTService]
                     self._ble.stop_scan()
                     print('Scan complete')
                     break
         self._ble.stop_scan()
-        return
 
-    def target_advertise(self):
+    def _target_advertise(self):
+        '''Advertises the target for the initiator to find'''
         self._ble.stop_advertising()
         print('Advertising')
         # Uart must not change on this connection if reconnecting
@@ -108,10 +126,8 @@ class BLE_Split(Extension):
             self._uart = UARTService()
         advertisement = ProvideServicesAdvertisement(self._uart)
 
-        try:
-            self._ble.start_advertising(advertisement)
-        except Exception as e:
-            print(e)
+        self._ble.stop_advertising()
+        self._ble.start_advertising(advertisement)
 
         self.ble_time_reset()
         while not self.ble_rescan_timer():
@@ -123,11 +139,12 @@ class BLE_Split(Extension):
         self._ble.stop_advertising()
 
     def ble_rescan_timer(self):
+        '''If true, the rescan timer is up'''
         return bool(ticks_diff(ticks_ms(), self._ble_last_scan) > 5000)
 
     def ble_time_reset(self):
+        '''Resets the rescan timer'''
         self._ble_last_scan = ticks_ms()
-        return self
 
     def _send(self, update):
         if self._uart:
@@ -154,4 +171,3 @@ class BLE_Split(Extension):
                 return update
 
         return None
-
diff --git a/kmk/extensions/layers.py b/kmk/extensions/layers.py
index be60de6..8cd7321 100644
--- a/kmk/extensions/layers.py
+++ b/kmk/extensions/layers.py
@@ -1,8 +1,20 @@
+from micropython import const
+
 import kmk.handlers.modtap as modtap
 from kmk.extensions import Extension
 from kmk.key_validators import layer_key_validator, mod_tap_validator
 from kmk.keys import make_argumented_key
-from kmk.kmktime import ticks_diff, ticks_ms
+from kmk.kmktime import accurate_ticks, accurate_ticks_diff
+
+
+class LayerType:
+    # These number must be reserved for layer timers.
+    MO = const(0)
+    DF = const(1)
+    LM = const(2)
+    LT = const(3)
+    TG = const(4)
+    TT = const(5)
 
 
 class Layers(Extension):
@@ -49,6 +61,13 @@ class Layers(Extension):
             on_release=modtap.mt_released,
         )
 
+    start_time = {
+        LayerType.LT: None,
+        LayerType.TG: None,
+        LayerType.TT: None,
+        LayerType.LM: None,
+    }
+
     def df_pressed(self, key, state, *args, **kwargs):
         '''
         Switches the default layer
@@ -86,7 +105,6 @@ class Layers(Extension):
         '''
         state._hid_pending = True
         # Sets the timer start and acts like MO otherwise
-        state._start_time['lm'] = ticks_ms()
         state._keys_pressed.add(key.meta.kc)
         return self.mo_pressed(key, state, *args, **kwargs)
 
@@ -96,24 +114,25 @@ class Layers(Extension):
         '''
         state._hid_pending = True
         state._keys_pressed.discard(key.meta.kc)
-        state._start_time['lm'] = None
         return self.mo_released(key, state, *args, **kwargs)
 
     def lt_pressed(self, key, state, *args, **kwargs):
         # Sets the timer start and acts like MO otherwise
-        state._start_time['lt'] = ticks_ms()
+        self.start_time[LayerType.LT] = accurate_ticks()
         return self.mo_pressed(key, state, *args, **kwargs)
 
     def lt_released(self, key, state, *args, **kwargs):
         # On keyup, check timer, and press key if needed.
-        if state._start_time['lt'] and (
-            ticks_diff(ticks_ms(), state._start_time['lt']) < state.tap_time
+        if self.start_time[LayerType.LT] and (
+            accurate_ticks_diff(
+                accurate_ticks(), self.start_time[LayerType.LT], state.tap_time
+            )
         ):
             state._hid_pending = True
             state._tap_key(key.meta.kc)
 
         self.mo_released(key, state, *args, **kwargs)
-        state._start_time['lt'] = None
+        self.start_time[LayerType.LT] = None
         return state
 
     def tg_pressed(self, key, state, *args, **kwargs):
@@ -143,22 +162,23 @@ class Layers(Extension):
         Momentarily activates layer if held, toggles it if tapped repeatedly
         '''
         # TODO Make this work with tap dance to function more correctly, but technically works.
-        if state._start_time['tt'] is None:
+        if self.start_time[LayerType.TT] is None:
             # Sets the timer start and acts like MO otherwise
-            state._start_time['tt'] = ticks_ms()
+            self.start_time[LayerType.TT] = accurate_ticks()
             return self.mo_pressed(key, state, *args, **kwargs)
-        elif ticks_diff(ticks_ms(), state._start_time['tt']) < state.tap_time:
-            state._start_time['tt'] = None
+        elif accurate_ticks_diff(
+            accurate_ticks(), self.start_time[LayerType.TT], state.tap_time
+        ):
+            self.start_time[LayerType.TT] = None
             return self.tg_pressed(key, state, *args, **kwargs)
 
     def tt_released(self, key, state, *args, **kwargs):
-        tap_timed_out = (
-            ticks_diff(ticks_ms(), state._start_time['tt']) >= state.tap_time
-        )
-        if state._start_time['tt'] is None or tap_timed_out:
+        if self.start_time[LayerType.TT] is None or not accurate_ticks_diff(
+            accurate_ticks(), self.start_time[LayerType.TT], state.tap_time
+        ):
             # On first press, works like MO. On second press, does nothing unless let up within
             # time window, then acts like TG.
-            state._start_time['tt'] = None
+            self.start_time[LayerType.TT] = None
             return self.mo_released(key, state, *args, **kwargs)
 
         return state
diff --git a/kmk/kmk_keyboard.py b/kmk/kmk_keyboard.py
index 65e5751..cfad3e7 100644
--- a/kmk/kmk_keyboard.py
+++ b/kmk/kmk_keyboard.py
@@ -45,7 +45,6 @@ class KMKKeyboard:
     # overhead (the underlying list was never used anyway)
     _active_layers = [0]
 
-    _start_time = {'lt': None, 'tg': None, 'tt': None, 'lm': None}
     _timeouts = {}
     _tapping = False
     _tap_dance_counts = {}
@@ -68,7 +67,6 @@ class KMKKeyboard:
             'coord_keys_pressed={} '
             'hid_pending={} '
             'active_layers={} '
-            'start_time={} '
             'timeouts={} '
             'tapping={} '
             'tap_dance_counts={} '
@@ -90,7 +88,6 @@ class KMKKeyboard:
             self._coord_keys_pressed,
             self._hid_pending,
             self._active_layers,
-            self._start_time,
             self._timeouts,
             self._tapping,
             self._tap_dance_counts,
@@ -407,7 +404,6 @@ class KMKKeyboard:
 
             if self._old_timeouts_len != self._new_timeouts_len:
                 self._state_changed = True
-
                 if self._hid_pending:
                     self._send_hid()
 
diff --git a/kmk/kmktime.py b/kmk/kmktime.py
index 39381c8..18b62a8 100644
--- a/kmk/kmktime.py
+++ b/kmk/kmktime.py
@@ -1,29 +1,23 @@
-import math
 import time
 
-USE_UTIME = False
-
 
 def sleep_ms(ms):
-    '''
-    Tries to sleep for a number of milliseconds in a cross-implementation
-    way. Will raise an ImportError if time is not available on the platform.
-    '''
-    if USE_UTIME:
-        return time.sleep_ms(ms)
-    else:
-        return time.sleep(ms / 1000)
+    return time.sleep(ms / 1000)
 
 
 def ticks_ms():
-    if USE_UTIME:
-        return time.ticks_ms()
-    else:
-        return math.floor(time.monotonic() * 1000)
+    '''Has .25s granularity, but is cheap'''
+    return time.monotonic() * 1000
 
 
 def ticks_diff(new, old):
-    if USE_UTIME:
-        return time.ticks_diff(new, old)
-    else:
-        return new - old
+    return new - old
+
+
+def accurate_ticks():
+    '''Is more expensive, but good for time critical things'''
+    return time.monotonic_ns()
+
+
+def accurate_ticks_diff(new, old, ms):
+    return bool(new - old < ms * 1000000)
diff --git a/user_keymaps/kdb424/corne.py b/user_keymaps/kdb424/corne.py
index e522491..e8f8f13 100644
--- a/user_keymaps/kdb424/corne.py
+++ b/user_keymaps/kdb424/corne.py
@@ -23,7 +23,7 @@ LT2_SP = KC.LT(3, KC.SPC)
 TAB_SB = KC.LT(5, KC.TAB)
 SUPER_L = KC.LM(4, KC.LGUI)
 
-keyboard.tap_time = 500
+keyboard.tap_time = 320
 keyboard.debug_enabled = False
 
 # TODO Get this out of here
@@ -58,7 +58,7 @@ keyboard.keymap = [
         KC.GESC,  KC.QUOT, KC.COMM, KC.DOT,  KC.P,    KC.Y,                      KC.F,    KC.G,    KC.C,    KC.R,    KC.L,    KC.BSPC, \
         TAB_SB,   KC.A,    KC.O,    KC.E,    KC.U,    KC.I,                      KC.D,    KC.H,    KC.T,    KC.N,    KC.S,    KC.ENT, \
         KC.LSFT,  KC.SCLN, KC.Q,    KC.J,    KC.K,    KC.X,                      KC.B,    KC.M,    KC.W,    KC.V,    KC.Z,    KC.SLSH, \
-                                        KC.LALT, SUPER_L, LT1_SP,   LT2_SP,  KC.LCTL, XXXXXXX,
+                                        KC.LALT, SUPER_L, LT1_SP,   LT2_SP,  KC.LCTL, KC.N0
     ],
 
     # GAMING
@@ -117,7 +117,7 @@ keyboard.keymap = [
         _______, KC.F9,   KC.F10,  KC.F11,  KC.F12,  _______,                     _______, _______, _______, KC.LBRC, KC.RBRC, KC.LSHIFT(KC.INS), \
         _______, KC.F5,   KC.F6,   KC.F7,   KC.F8,   _______,                     KC.HOME, KC.LEFT, KC.DOWN, KC.UP,   KC.RGHT, KC.END,  \
         _______, KC.F1,   KC.F2,   KC.F3,   KC.F4,   _______,                     _______, _______, _______, _______, _______, KC.BSLS, \
-                                            _______, _______,  _______, _______,  KC.DF(0),   KC.DF(1),
+                                            _______, _______,  _______,  _______, KC.DF(0), KC.DF(1),
     ],
     # GUI
     # ,-----------------------------------------.                    ,-----------------------------------------.