What is this?

I don;t think that I'm alone in admitting that I've been there and more than once too. I seem to be incapable of remembering lesons, like measure twice cut once etc.
Mike
Which reminds me of the trainee clerk told to double-check calculations. She said: "I triple-checked, and these are my three answers..."
 
Did much the same last winter, ( not quite so drastic) but used a 140mm hole cutter on the internal moulding of my Sadler,,,,,,,to provide an access underside to cleat bolts/nuts, carefully marked the drilling point, squirmed out of the quater berth, wriggled back in head first, drill in hand and immediately mistook an old mark for my new one and drilled through, ‘whoops’ not the right place so have had to repair the wrong hole and then cut the new one in the right place. Fortunately it’s right down the aft end of the quarter berth and not easily noticed. Except by me!
 
I have that T-Shirt to. Took me a while to realise the hissing sound was the gas pipe I had just drilled through. Someone far vleverer than me said ........................... "Make mistakes by all means, but never make the same mistake twice, always new ones" :)
 
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