[juan (the ping-pong ref.)]

I'm not sure if you can just do that in every day life. But you can practice on the drums untill it becomes second nature. play down the toms, that will get your left hand working. Another way is to do a simple 1-2..3 ( that was the only way i could think or explaining it). ex. hit the snare twice and then tom1 once, then repeat with tom 2 and so on.

those exercises should get your left hand back up to speed.