Does X chocks help stablity?

I have used them for about a year now and I like them a lot. They're easy and the trailer is rock solid, meaning I can walk around at night without waking up my wife. As for the movement, when I drop the tongue on the ball I have to pull the TV forward to pull the ball so that I can set the locking lever all the way down. It's just a quirk in my rig. When I do that, the trailer always stops my TV without moving a bit. Granted, I don't exactly floor it, but there's a definite rolling resistance from my X's. If I were to park on a steep incline, then I'd probably use another chock as well, just for safety's sake, but I generally choose spots that are as level as possible.