[Mystic]

I have this problem, too. I've kind of sluiced out that this is because my brain knows what it's supposed to say -- So if I leave words out in the text, my brain just automatically fills them in when I'm proofing. Usually, I discover the missing words or odd syntax MUCH later on when I'm rereading something.

This happens to me frequently. Generally if something is more than a page in length I wait a few hours after typing it to reread or proofread so that it's no longer fresh on my mind and my brain won't fill in any word gaps.

Also, I generally give people with extremely poor grammar/spelling the benefit of the doubt and hope that English is their second language, they had a very poor education growing up, or I invent some other problem that could be causing it (i.e. They have no arms and are using a mediocre voice to text software).