Who ever decided that stupider wasn't a word was just an asshole so that when you say something like "You couldn't be any stupider" you're really just make yourself look dumb.
Though "stupider" would probably be technically correct. But it just sounds stupider than more stupid. :d
Stupider is a word. According to traditional grammar rules, only words with one syllable would have the 'er' suffix. Dumber. Speech is colloquial, when something is used often enough, it becomes a word. Grammar rules are based on acclimation. http://dictionary.reference.com/browse/stupider
There is nothing Ironic about rain on ones wedding day, it just sucks. It's not ironic to get a free ride when you've already paid, that's just a catch 22. A traffic jam when you're already late, isn't ironic, again it just sucks. A traffic jam slowing a person down is only ironic if that very traffic jam was expected to some how make you early...