Due to the types of errors (e.g., "Festers" instead of "Posters" in one message) in his messages, I would say he writes his messages on a smart phone that uses hand-writing recognition software.
However he does it, he appears to be too busy to go back and proofread the messages before he sends them. :)
¶ he also types everything from a phone supposedly
Market Data 
Markets 
AI
