Yeah... I'm a little disappointed, too... there were just
so many cool possibilities...
I still say, though, that the mistake wasn't ours... after all, while Evans may be a common surname in real life, in the context of her story, it would make more since to strictly avoid that surname unless there was a meaning behind it... Potter's a common surname, but she wouldn't dream of having a non-important character with that last name, because the first thing we'd all think would be "?????????!!!!!!!!!!!!!!?????????!!!!!!!! THERE'S ANOTHER POTTER????!!!!!??????!!!!!"
