Doc: comments for extra clarity

docs/feature_split_keyboard.md

@@ -313,6 +313,7 @@ QMK's split transport allows for arbitrary data transactions at both the keyboar
 To leverage this, a keyboard or user/keymap can define a comma-separated list of _transaction IDs_:
 
 ```c
+// *_SYNC_* names can be called whatever you want, so long as they are passed to transaction_register_rpc with the function they apply to
 // for keyboard-level data sync:
 #define SPLIT_TRANSACTION_IDS_KB KEYBOARD_SYNC_A, KEYBOARD_SYNC_B
 // or, for user:
@@ -395,6 +396,7 @@ void keyboard_post_init_user(void) {
 
 void housekeeping_task_user(void) {
     if (is_keyboard_master()){
+        // 24 is arbitrary int8
         transaction_rpc_exec(USER_SYNC_A, 24, NULL, 0, NULL);
     }
 }