The misspellings and grammar errors may be intentional to obfuscate the exact thing you postulate.
My point is that in time this guy's tendency to misspell words or use the wrong word in context is going to develop a pattern. Bad guys can say, "Who do we know who uses the word "stationary" instead of "stationery"?
The answer to that one is "lots of people", but each one has a person attached to it.
Eventually someone says "I know a guy in Congressman X's staff who says "alot" instead of "a lot"...
There are other examples too, which would contribute to a developing pattern, I just don't care to go back and cite them all again.
Maybe I might start making note of them from here on, though.
Might be both. Coded misspellings and poor spelling. Lots of very brilliant people are poor spellers. English is a horrible language in terms of spelling.