In advance of what? I personally don't do street photography, but was a photojournalist for almost 20-years and can tell you from experience that anything can happen anywhere, in any direction. Regardless of the appropriateness of artificial light, it is simply not possible to "plan" lighting for random and spontaneous events. However, if you do have that gift, I'd gladly appreciate the winning numbers for next weeks lottery 
Predictions aside, Russ is absolutely correct about the negative issues with using artificial lights in such situations. I once heard a street photographer compare himself to a spy. He's only effective if nobody knows he exists.
That's why I took to hanging around the local bar that does the jazz stuff; after three hours of gigging those guys didn't care if I was there or not, and over the next few gigs I became part of the chat and have even built up some casual friendships that, in a small town, have already opened my eyes to the subterranean interconnections here. Though I can be seen I am still invisible in the best possible way for a snapper. Maybe the fact that this is a tourist town helps one become assimilated fairly quickly ... may be far more difficut in a rural spot. On the other hand, none of those guys uses a trombone.
(Also, I now wonder how anything got done prior to the concept of the website. Wish I'd met Fred sooner!)
Rob C
