[quote name='RhysP' post='1012405' date='Nov 4 2010, 06:43 PM']I'm pretty sure he can read music & has some knowledge of theory - as a child he was a chorister at St. Andrews church in Wembley (which at the time Squire was a member was regarded as the best choir in Britain) & would have been required to sight read for this.[/quote]
I've no idea how much Squire can read but the point made above seems to me likely - even if he hasn't been practicing his reading skills regularly since then.
For what it's worth, Bass Player magazine called Squire 'a serious student of harmony' and when they asked who were his biggest harmonic influences he said: 'I got a big education from my years in church choir, which had a really good choirmaster. He taught us a lot about the relationship between vocal lines and bass lines in a choir setting, and I think I adapted a lot of that knowledge into playing bass and singing. I’ve always been very aware of the relationship between the bass and the top melody line.' ([url="http://www.bassplayer.com/article/basso-cantantecontinuo-chris/jan-09/91289"]Source[/url])
I can't say I'm particularly a fan of Yes or Squire, although I wouldn't doubt his abilities.