I often hear complaints (from battle boards everywhere) that the Speed Force is a pretty dumb way to give excuses and let Flash's powers work without real world consequences. I'm on the other side of this. It's a comic book character, so writing something like a Speed Force to not only explain why Flash doesn't tear himself or the world apart when he runs so fast (or any other issue high speed running would cause) is not only convenient, but entertaining as hell! Not sure why so many people tend to see that as some stupid concept.
I feel like people's issues are less a hand waving of physics and more how the authors tend to use the speed force as an ad hoc justification for any number of random things they want to have happen even if it makes no sense whatsoever. See the creation of the new 52.