flatback,
FWIW, I would completely trust Jon's judgement on anything bass related, and as you point out he does work on not only a lot but most of the basses for players around L.A.
I also live in the Bay area now and I've yet to meet anyone that has the knowledge and collection of basses that Jon has down at World of Strings. He has a Czech bass I really like at the moment.
I live in the South Bay area (close to Cupertino) and there are no shops down here that specialize in bass. Stevens Violins in Willow Glen used to when Gordon Stevens owned the shop, but there's a guy named Vance that bought the shop from Gordon and all the cool basses that Gordon owned are now gone and replaced with cheap Chinese copies. Vance is one if the biggest @$$#O!E$ I know of, and doesn't want to work basses, so he only is looking to make a quick buck.
It seems that Allan Droyan seems to have moved up to Fort Braggs area and the "String Bass Shop" has somehow turned into the "Acoustic Bass Shop" and Alex Friedman runs it. I talked with him, but he has mostly new Chinese basses that vary in price from $2k-$5k. I'm not completely sure what their relationship is, but when I sent email to Allan Droyan he told me to contact Alex about vintage basses. He has a couple on consignment but nothing worth writing home about from his description. Alex at least seems competent to work on a bass.
Who do you have do work for you in the Bay area?
Jon Pedersen does excellent work, IMO, and I'm beginning to think it's easier to drive to L.A. and take a bass to him to have work done. From what you describe about putting a light dressing on the fingerboard doesn't sound like it would damage anything, IMO, but what do I know...;-)
You should call him and ask about that, he's always more than helpful in my experience.
I personally like the idea of cleaning and dressing the fingerboard, since a lot of sweat and dirt get together which is not a good combination. When you play, you're basically rubbing sweat into the wood. Nothing worse than when I had my vintage guitar store, sometimes you open a case and the guitar has smegma all over the neck...I hate people that don't take care of their axe...