Pushing off the rubber?

Last night at a clinic, a coach was telling pitchers to push off the rubber. Is this correct? Your power comes from the lower half he said so pushing off the rubber will allow your backside to explode.

what are your thoughts???

You can read a small bit about it in the pitching mechanics section under Question to NPA guys.

its okay to push off
but your timing’s got to be almost perfect
if not it will makyour rush if its done too early or too late