Actually, the most mistakes I've ever made when sending blurbs of texts was the several months before I figured out how to disable autocorrect on Tweetbot on my Mac. Man that was terrible. Kept having to delete tweets because I hit "Send" before fixing the autocorrected text.
Alas, if you frequently use two different languages and often mix them both in the same sentence (common among bilinguals) autocorrect is your absolute bane because it will always do the wrong thing.