shane-o wrote:saw a bike courier the other day on a FZ1 do a U turn in a space about the size of a bedroom, at speed, one handed, leant right over, and he didnt looked to of even clenched his butt cheeks let alone shift his weight 1/10th of an inch. Just looked where he was going, and had all the confidence in the world, its was lovely to watch

Actually, according to the MSF, in this situation you should shift your weight to the OUTSIDE to counterbalance the bike and lean it more towards the inside. I do this when making tight slow speed u-turns. I'm not sure how well it would work "at speed" though.
As far as leaning off the bike (towards the inside) while riding on the street, it isn't usually a good idea. Unless you are already at the most extreme lean angle and in danger of scraping metal or washing out the front wheel, it shouldn't be necessary either. Better to have that as an additional option if you need it while in a corner during an emergency.
I will admit that I used full leans while running the switchbacks up and down Mount Palomar in soCal. And I completely understand what you mean by feeling more confident in that position. The first few runs up the mountain, I was feeling really uncomfortable, and disappointed with either my bike or my skills or both. All of that went away once I started leaning off.