Re: Only cracking I have done is
Many years ago I had a friend at college who, for a kind of party trick, would easily pick the padlocks on student trunks. Took just a few seconds and you'd have to be watching quite closely to see he didn't have a key.
He never abused his ability, but he would pick a lock, then put it through a piece of paper on which he'd written "Get a better lock!".
I don't recollect witnessing it, but I think he also did that to bikes, and was dismissive of big heavy expensive D-locks that were really secure against being broken but could be quietly picked in a few seconds.