Here's a question I submitted to Ian Wallace via "Elephant Talk", the King Crimson newsletter, followed by Ian's response:

From....JAskelly@aol.com

I was told once by a very knowledgable gentleman that you sat in with the band Yes at one gig very early in their career (sometime in 1968, I believe.) Can you verify this? If so, do you have any recollections or details to share from that gig?

Thanks very much.

** Ian replies...

Yes, I did play with Yes. My first professional band was called the Warriors, and John and Tony Anderson were the lead singers. John who later changed his name to Jon formed Yes with Chris Squire. When I moved to London with my band Sleepy, Jon told us there was a room free in the house he was living in and we consequently moved in. Jon lived on the top floor, Chris Squire and Tony Kaye lived in the basement. We all became good friends and Bill Bruford and I would often hang out and talk drums. At some point, Bill decided to give up drumming and go back to university. Yes recruited another drummer.

One day Jon came knocking on my door in a panic. The drummer had had an accident and was in hospital and they had a gig that night and desperately needed a sub. I was the guy.

I remember really enjoying the gig and at one point Chris Squire turning to me in the middle of a song and shouting out "Do you want to join a band?" I thought long and hard about it. Two weeks before they were due to open for Cream's farewell concert at the Albert Hall, I had dinner with Yes' manager, Roy Flynn who almost persuaded me to join. But I felt too loyal to quit the band I was in and turned them down. Can you lend me a quid?