In addition to all of the UX issues that have been brought up here, there's also the problem of spaces in a user name. Sure, an algorithm could be written where

In addition to all of the UX issues that have been brought up here, there's also the problem of spaces in a user name. Sure, an algorithm could be written where the last broken up block of a string split by spaces in considered the password ... but then what about passwords with spaces in them?