It's natural for the right handed 90% of the human population to dismount to the left, horses as well as bikes, so that's where the stand is (on bikes, horses don't need them). I can only conclude that 10 mph is left handed or ambidextrous with some left hand bias.
This sort of thing doesn't only apply to bike riding, For example, I have a refuse bin room at the left of the front exit of my apartment block. It's outer door hinges left, the binmen approach from the right. But they, when right handed, pick up bins with their right hand beneath the right side of the bin and their left hand at the top left, as if to tip left, but the trolley bin they empty into is on the right, so they can't. If they were to try and pick up the bins the opposite way, they'd get crippled with muscle strain in no time due to the unnatural action.
So they don't empty the bins by tipping, they just pick up the contents if bagged and transfer them. If the contents are loose, they get left.
Of course the architect didn't realise that he should have put the binrooms on the right of the front doors of the blocks, only correctable now by the council only employing left handed binmen.
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