1) The rules for Machina Domini Interface (as per p. 141, Jihad: Final Reckoning) state that a BattleMech operating with such a system receives a -1 modifier to Piloting and Gunnery skills
2) The same rules state that a Machina Domini Interface requires the mechwarrior to be equipped with a standard or Buffered VDNI implant.
3) The rules for VDNI and Buffered VDNI(as per p. 129, Jihad Hot Spots: 3072) state that units being driven by warriors equipped with VDNI or Buffered VDNI get -1 to Gunnery, and -1 to Piloting for VDNI only.
Therefore, given that a Machina Domini Interface requires some form of VDNI, do the bonuses from the Machina Domini Interface stack with the bonuses granted by the VDNI implants?