Yes, Rene, seems like that could be the reason, at least I agree with you....ofcourse Yello/Boris could, like other techno bands, have recorded the music before performing live and then just "pretended" as he was playing it. But then again that would be wrong too....
Too late - I believe that's exactly what they did on the Yello Video Show. I have the video on VHS, which I watch every once in a while, and sure enough, other than Boris singing and Deiter making some weird noises on a keyboard, that's it for the live stuff. They had a lot of it prerecorded (like the drum sounds, and a lot of the synths). It's actually very comical/cheesy to see Deiter pretend to play one of the keyboards (i.e. he waves his fingers over it, not actually hitting the surface of the keys). :) But what a stoner flick! Oi, they have some of the most awesome psychedelic videos I have ever seen! Definitely a must-see for those who haven't seen it yet... Plus has a nice shot of Diane Brill doing something like a "Birth of Venus" thing in the beginning, hehe! Since Yello is studio-heavy, I agree that it would be difficult to recreate it as a live performance. On the other hand, I've seen some newer bands, like Plaid, do wonderful things from their Power Books live! Then again, one tends to wonder how much work are the artists are actually doing on the laptops to make it a live performance, and how much work are the laptops doing. :) My $0.02