After watching videos etc of the Revolution and especially Bobby Z, can someone confirm my suspicions that the Revolution used backing tracks?

You can see that more drums are hit that just what you see Bobb Z do. I wonder if they played with a backing track or at least a click track and bobby just kind of tapped allong and hit the cymbals. Also, in purple rain (i know its not live) you see Dr fink play the hi-hat on his keyboard, at the start of I would die 4 U. He couldn't keep this up for a whole song in perfect time and neither could bobby z live. Just because with electronic pads back in the 80s wouldn't have been that accurate to be able to do that for that long. you would get mis-triggers etc. So no doubt this would have been on a backing track.

Also watching the 1985 live video, it seems like they use 'something'...

does this interest anyone?

Yes, Yes definitely.
Bobby Z just mimed

gainsbourg said:

but he didn't just mime. There's stuff going on he didn't even mime to. he does hit stuff, he just doesnt play all that you hear.

The same with Sheila E. and other drummers Prince had in his band. There were always backing tracks, but they added live drums to it.

Drum machine.

There are very few performers who do not use DATs/backing tracks! It does not detract from anyone's ability or performance - in fact, it is harder to play with a backing track or sequencer becuase you absolutely have to be on the nail - human timing characteristicly wavers slightly.

More often than not, and as is the case with Bobby Z, the main rhythm and any ad-libbing/filling is performed by the drummer and then embellished by tracked percussion loops, if there is no live percussionist.

Prince and the Revolution did not mainly use backing track. They used SEQUENCERS and DRUM MACHINE PROGRAMING. That is how the arangment coud be changed on the spot when prince called out accents and turn-arounds. Bobby Z. had a great talent of being able to stop and stat the Linn Drum to whatever Prince called out. I have heard backing tracks used on "When Doves Cry"and for interludes. With the NPG, Prince had Morris and Tommy trigger backing vocals and samples LIVE.