On Logic and Alternate Universes

[Excited Penguin]

I think he's merely using the mathematical blunder as a symbol for a state of things (from a hypothetical parallel universe)  that is alien to ours. Bad choice of exposition by example in this case. If one wishes to discuss something one should take care to best explain what he means to discuss, especially after the other parties have expressed their confusion, however indirectly.

I figured it's too late for that. I wouldn't want the confused parties to claim victory for their straw man if they see me "backing out" of bloody 2 + 2 = 5 being a thing somewhere else.

It's never too late if your goal is discussion. You do this well(or try to)  and I'll take your side against anyone who gives you a hard time for it.