About running shoes. It seems that we should aim for shoes with no "shock absorbers" whatsoever. Though aren't these shock absorbers useful in preventing injury? I mean.. If I'm running on pavement (side walks etc), It's quite a tough surface and the knees are under great pressure. Wouldn't shoes with no shock absorbers be a little less useful for that purpose?

I know that primal wise we should always aim for natural, meaning as close as we can get to barefoot. Though that probably applies for walking, wouldn't running be safer with shock absorbers?