I know when I use my foot pedal, I wind up twisting it 90 degrees so it gives the sole of my foot more room to work - more control so it doesn't run out of control. It does drive me nuts sometime to try to push and get no response, however!
Once I get it in the right spot, I hate to move around because it moves on the carpet. I'll have to get one of those plastic mesh type mats to keep it in place.