Here is a good article that your friend might like on how mds works.

http://www.canadiandriver.com/2005/0...on-systems.htm

From what I am reading it needs to be deactivated in the ECU, If not for any other reason that because when it switches on and off it changes the way the electronic throttle control works. My thought is that if you HAVE to disable it in the ECU anyways with a SC or DSP, Why bother getting your hands dirty and messing with the mechanics?

 

When the ecu senses the lifters in a "not ready" state, it simply disables mds. No side effects. Guys have been doing this since early 07 (pre mds tuner delete) with no problems.