Ed,
I was using 1 of those screw type anchors and it was still solidly attached to the dolphin striker with the boat upside down. It was one of the short ones, but I had dug a deep hole first, screwed it in then as far as I could go, then filled in the hole, so the top was at least 2 below the surface. I also had my heavy cat trax tied to the front of the bows to add more weight. They also were still firmly tied to the bows the next morning.
When I left for the site, the forecast was for the wind to continue to die slightly and back around more west over night. I had to completely string up the whole boat and was supposed to help with the event set-up, so was trying to get a head start on rigging for Saturday. Turned out to be a bad call. I think what really got us was that the east wind and full moon brought the tide way up. The weed line was above where we were tied down and the trailers were all partially submurged. The waves most likely shifted the boat and the wing mast took it from there.
That's what I get for trying to do things in advance; why couldn't I have procrastined as ususal (another case of positive reinforcement for a bad habit). I lucked out, other than the broken stick, there was not so much a scratch on the boat. Timbo ended up with the bad deal.