I’m guessing that people used to put up with a great deal more rubbery bits in order to get enough protein…not like us modern softies.I have old recipes for what we would now called stews, but contain things like whole wee birds, hares, and oysters, all cooked in a lidded cauldron, I wonder if cooking the limpets and then letting them stew would end up relaxing the muscle (which is really all it is that's edible) enough to stop it being like a wee dod of rubber.