Well, I am using a new cinch now, I cinched short pulls and walked him around some. We had no "going down" incidents at all this week. I actually faked him out once by putting a lead rope on a loose (no saddle) cinch and tightened slightly over a saddle pad. He looked confused but didn't go down.
My overall judgement is it is a behavorial issue more than anything. I am just going to have to be ahead of him as this can do some damage to saddles, let alone him!