Parallel commands that depend on the same subsystem?

[BigJ]

If A and B both "require" C in your case, either you are trying to control the same physical parts of the robot (motor controllers, solenoids, etc) with 2 commands (bad and can have unexpected results), or your subsystem has 2 different (sets of) physical parts that the commands are controlling (in which case you should refactor said subsystem into 2 subsystems).