This is my opinion. Guys like Webcke who have little experiance, like anyone else starting out in anything, has to get experiance, not in a commercial facility but with a private studio or good trainer that can either do an internship or mentor under. I've never worked anywhere else but from what I have heard you really don't learn much exept on how to sweep and put weights away.
This would be hard to pull off in Manhattan where the landscape is dominated by chains. A trainer just starting out would be severely limiting his options.
My experience is probably dated, as I haven't been a trainer for almost 20 years, but, I worked at a very large health club: 5000 members. I started out as an instructor and eventually became a trainer. I have to say I did learn alot from other trainers. Maybe the most important thing I learned was to be patient with people who weren't athletically inclined.