You've got to start thinking in terms of "risk vs. gain".
Was the risk of damage from the old wharf worth the gain of calibrating your wind instruments? Maybe... depends on your skill level. Be objective about your abilities.
Was the risk of further damage worth the gain of recovering a nasty old fender that you were going to throw away anyway? Nope. Not at all. Not even a little bit. So you learned from your mistakes which is great! Slow down, be deliberate, think "risk vs. gain" next time you're out there.
I've been reflecting on this, and I think this model really resonates with me. I've learned through my training and profession to be very quantitative about things. I think that consciously deciding to consider the risk, every time I try something risky, might really help improve decision-making.
The part I've been considering the most, though, is that I don't really have a good way to assess the risk of various activities. I'm not experienced enough to know how things can go wrong. In this case, it seemed that docking to a wharf wasn't much different from other stuff I've docked to before; what I didn't consider were the effects of wind. It's obvious in hindsight, but ahead of time, it's hard to really see everything that can go wrong.
Tied up in this is basically the reality that I'm going to have to keep pushing myself out of my comfort zone if I'm going to continue to improve my sailing skills. I have to try new things, that seem slightly harder than things I've already done.
I still can't believe I went back for that crappy fender though. I have no idea what I was thinking.