Gmail's user experience is terrible in many ways, but I don't think it's fair to excoriate them for adding a feature that's not so idiot proof that not even one

Gmail's user experience is terrible in many ways, but I don't think it's fair to excoriate them for adding a feature that's not so idiot proof that not even one in a hundred users will misapprehend how to use it. That school of ultra-spacious user friendly designs for the lowest common denominator is how we ended up with the nightmare that is the current Gmail interface.