Yeah, some of it really doesn't work. There are some amazing versions of Tear on that tour though where it really comes together, others not so much.
The straight piano improvisation works much better than some of the other synth sounds he would throw into the mix though. Those haven't dated well, and at the time probably sounded pretty naff as well.
When him and BC work well together though, it's some of the best stuff SP have done live.