It's HEEL and toe. It's just bliping the revs for smoother down shifts. Personally, I use the side of my foot not the heel. Just watch the "foot cam" in the video, practice everytime you slow down at a stop light, rev match through all the gears while you brake. Eventually you'll get better.
No reason for heel and toe'ing when cone dodging if thats your main sport. You should only shift once, and thats 1st to 2nd. Unless you are "stompy", then you can shift from 2nd to 3rd, and then back down.
The rev matching part is much easier if you have a louder than stock exhaust. Also, when you brake don't rest your heel on the floor. Put it close to the top of your brake pedal. You'll have less leverage on the the pedal which makes it easier to modulate your inputs, AND it will be easier to pivot out your heel to hit the gas. Practice makes perfect!
Cool video I've found that my legs are too long for heel-toe in the wrx. I don't have enough room to get my foot positioned how it needs to be. The steering wheel gets in the way.
I find that I have to adjust the wheel up higher than I would normally have it for driving if I want to heel toe. My wife always keeps it up high, so I got used to it, and can heel tow easier now. Having the wheel higher also reminds me to try to get in the habit of always keeping both hands on the wheel when not shifting -- Brian