Hi Dave, Sam,
Thanks for the answers.
Dave, believe it or not, I am not much of a FMA kind of guy, I know a bit, but not as much as most JKDers.
My instructor teaches in more of a “Wing Chun” type of structure, and I enjoy it. We end each class with Sil Lim Tau, and enjoy training in Wing Chun. I think that is why you find me more WC forums these days then JKD ones. 
Anyway, I do a few of the switches, but my favorite is one called the beat/pak switch. It is fun to do, and I feel it teaches some great lessons.
As far as the Lop Sau drill goes, I look at it as more of a drill to in grain the reactions to:
A - Having a Lop Sau preformed on you.
B - Dealing with the structure and timing of the bong sau.
Sadly, I feel that to call this drill the “Lop Sau” drill really does it a misservice. In the way we do it, it is more of a bong sau/lop sau drill.
Again, this maybe just we the drill, I can not, and do not speak for all of JKD, just my little segment of it.
In your response, you said that you feel the drill is more of a “speed and coordination drill”. That’s interesting in that I never really looked at the speed aspects of the drill. My instructor tends to talk more of the timing of it, rather then the speed.
That’s what I love about this forum, although the Wing Chun is very new, it is really starting to have some great, informative posts in it.
All the best,
BIG Sean Madigan
www.bigjkd.com
[This message has been edited by Sean Madigan (edited 08-31-2000).]