Right you are. And under his real name of David Kaffinetti (shortened to Kaf in the movie credits) he was the pianist for the early '70s prog rock band Rare Bird.
David. He’s such a rockstar! Yum! All pouty blondeness. 'Course he’d have to just shut up and have fun, since he’s not all that much brighter than the others. For conversation, Derek.
Though they all look surprisingly good in tight pants.
Fair enough… I stand corrected. One of those memories that is so false I can actually see ‘Derek’ saying it!
I ought to know really - never begin a correction with: “I think you’ll find…” or you may end up as a friend did - in a wine bar, holding a large glass, and announcing loudly to the bargirl:
“Actually, I asked for Chardonnay.”
She looked at him blankly - Fate giving him one last chance to bale out. He, rejecting all last chances for redemption, hanged himself by following up with:
"I think you’ll find that Chardonnay is a red wine…"
I still smile thinking about that ten years later.
Don’t feel too bad, people seem to screw up who says that line a lot. I had a philosophy professor who used to quote it in lecture as an illustration of the Epicurean philosophy, and he always wrongly attributed it to Mick Shrimpton. He seemed to have a clear visual memory of the scene, and always described it as taking place during the bathtub interview. I corrected him once (outside class), but I don’t think he really believed me!
*Heh heh heh, poor guy. 
Hijack:
I was having lunch at a the Hyatt in San Diego where my company was holding its convention a few months ago. I was having pasta, and I asked if they had a house red.
“You mean like wine?”
“Uh, yeah. Like wine.”
“I’ll go check.”
He came back and offered me a chardonnay.
Anyone else who wishes to offer their opinion is welcome to join in, but here are the results so far:
Third Place: David St. Hubbins, with one vote and three secondary mentions. He’s got the look, he’s got the name, but unfortunately he’s also got terrible taste in women. Jeanine has been a real handicap in this competetion.
Second Place: John “Stumpy” Pepys, not officially in the contest, but would have received two votes if he were. Not bad for a great tall blond geek with glasses who died in a mysterious gardening accident and only appeared in the film for a few moments. RIP Stumpy.
First Place: A tie between Nigel Tufnel and Derek Smalls, with five votes and two secondary mentions each. Nigel impresses with his ingenuousness, his haberdashical skills, and his willingness to take it to eleven. However, dark horse Derek (long considered the underrated Tap) wins equal acclaim for his conversational ability, levelheadedness, and most importantly, his grand moustache.
Unfortunately, Derek is out of circulation for the time being. Better wait until that sore goes away, ladies…