Do you have a big backing plate that spans the large bolt and the 2 smaller ones? Or just washers?
My O’Day 322 has some beefy aluminum backing plates under the stanchions. A pain to get the bolts in from the top, and lined up with the holes in the backing plates, but it is fairly stout.
I snagged my docking loop on my gate stanchion (which has a brace) while backing out of my slip one day. It bent the SS stanchion, and drove the brace through the fiberglass deck

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I used some Six-10 thickened epoxy to fix the hole, and added a large washer on the brace leg since it didn’t have much of a shoulder on top of the fiberglass. But the backing plate worked great!
I have guys that sit around and drink beer on my dock. They always get up to give me a hand when I come in… on a stiff cross-wind day, I really appreciate their help. But I usually say “hey, hand me the docking loop on the hook, and I am good“. That way they can help, without yanking on my stanchions.
Greg