I'm another proponent of using the front brake almost exclusively, except in unusual situations. Bikes like the S10 and S1000RR are now smart enough to do the light feathering of the rear brake as needed which is just fine with me - one less thing to worry about.
When I asked Keith Code one time about use of the rear brake he said that he generally advises novice to anything-but-expert riders to think of it as an emergency brake to be used when the front brake fails. On the street, he advises almost never using the rear brake. That being said, I believe there are some situations, especially in the dirt, where it has its place.... for example to help rotate the bike by sliding the back end in the dirt, or when coming down steep inclines.
My basic philosophy about fast street riding is to reduce the variables and keep things as simple as possible to avoid errors. The biggest problem the bike faces in consistently negotiating corners at a good pace is the nut behind the handlebar. Do almost all of your braking straight up/down before the corner, then release the brakes at corner entry and get on the throttle - mixing trail braking into the equation may allow a little more corner speed and be ultimately faster (especially at the track), but it requires the trading off of braking traction vs. cornering traction in a situation where any significant error likely puts you on the ground without any chance of saving it (ABS might help, but has its limits in a lean). And corner entry is the place where being a little conservative and not being at the limit pays dividends when the corner doesn't work out exactly as planned, as many don't. I don't like diving into a corner knowing I need to scrub off more speed while in the corner. It's easy to add speed, hard to get rid of it.
And not using the rear brake allows you to keep both balls of your feet on the pegs, without repositioning your right foot at every corner - another thing that destabilizes the bike and is an opportunity for error. You only have three controls to worry about - throttle, brake lever, and pushing on the bar as required to get the lean you need.
All this being said, cornering and braking technique are not a one-size-fits-all situation and you need to find a system that works well for you individually. You need to be comfortable and relaxed. Very attentive and concentrating, but relaxed and not worrying.
- Mark