Likely because he held a similar lecture in the Tippit thread last year.
https://www.jfkassassinationforum.com/index.php/topic,4116.msg158279.html#msg158279
He tried to do the same in a conversation I had with him about Oswald being on the 6th floor when the shots were fired and coming down the stairs within 75 seconds after the last shot.
He couldn't prove that Oswald was on the 6th floor at 12:30 PM or that he came down the stairs, so he started to use circular logic.
1. Oswald was seen on the second floor door by Baker within 75 to 90 seconds after the shots, which somehow "proves" that he must have come down the stairs
2. Oswald came down the stairs which "proves" that he must have been on the 6th floor.
It's laughable, but what is worse is that he actually believes his reasoning is logical.
You'll get a better conversation out of a brick wall.