AI Servo + Continuous Shooting Mode For People/Candid

I was thinking, especially with shallow DOF's, wouldn't it be better to shoot candid and journalistic photography with AI Servo? I was shooting it with one shot, and I realized that a fair amount of my shots were comming out soft. I thought at first that it was because my apeture wasn't deep enough. (shot f/2ish) then I realized, holy crap, in the time it takes me to push that button these people are probably comming about 1-2 inches closer to my lens and throwing off the focus....

Another thing, continous shooting would probably be better huh? It seems to be that the facial expressions are what make the photograph, and they change so darn fast! I see one I like, then I photograph it and find that the person blinked or something. So maybe I should shoot in 2-3 shot bursts in continous mode...

What do you guys think? Any other recommendations?

Dunno hw you're going to get candids with the 20D in burst mode, unless you want candids of the photo-shy swinging their fists at you when the motor starts to rip. AI-Servo, however, would be a good choice.

Hm, the 20D is so fast that I don't think 2 clicks would be anymore distracting or alerting than 1.