Which reminds me of the following.
I have a good friend who's a fifth grade teacher. From time to time, he will (intentionally) include made-up or mangled words in instructions or questions on tests that are unrelated to English, grammar or the like. Consider, for example, the word "wouldnt've" (or "wouldn't've") The goal: how many perplexed looks and upraised arms can he get?
He sometimes uses a simpler alternative: just substitute the word "of" for the word "have" in the phrase "would have" or "should have." "The Athenians should not of invaded Sicily. Discuss."