THE OLD GREY WHISTLE TEST was a British TV music show, which presented live performances. Is this correct?

There are numerous CD's available using that rubric. Does anyone
know which contain recordings of performances from the show???

I've seen a RHINO/BBC CD of FOLK performers - It appears to be
drawn from commercial albums, not from the performances
on the OGWT show. Can anyone confirm that (or provide a reference
indicating they are performances recorded for the broadcast) ??

THANKS!
Best wishes, Thomas.