We’ve been trying to solve one a week (Monday’s, so usually Rufus) over lunchtimes at work, usually 2+ of us. I think we’re better than when we started a couple of years ago, but we still almost never finish one over five days.
But, given more quiet thinking time (ie, on holiday, with no distractions), I have occasionally got close to finishing one. So, given I knew nothing about them not so long ago, that’s some progress.
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