Well, the brake would still slow down the wheels anyway, just don't give it a lot of power so you don't come to a halt every time you try to drift through a corner. Then give it a higher enginebrake so you can slow down when you need to just by not pressing forward. Trying to use your crouch button to drift instead of drifting when you use the hard brake (and losing traction as you are (figuratively in this case) locking up the wheels) might be awkward to get used to.