Antirockballfruitcake doesn't have a single functioning braincell.
Warning for gaslighting.
Telling the truth is not gaslighting.
That may or may not be true. But given your original statement above, how is that relevant?
I would have thought it obvious that someone who thinks Antarctica and Space don't exist is, ipso facto, a sandwich short of a loaf. Or as Markjo notes, Antirockthingo, is only here to troll.
Either way it's nothing to do with dipstickone. The way he inserts irrelevant comments into threads is quite frankly a bit creepy.
PS. Your signature pretty much sums it up.
Okay. But being "a sandwich short of a loaf" =/= not having a single functioning brain cell.
One might be true depending on what it actually means. The other is objectively false - unless he's a real dead zombie! But if you believe in zombies .... 
I suspect you are doing a "Sheldon Cooper" impersonation, so I'll leave you to research the phase "sandwich short of a loaf" and I think you'll find it actually does co-relate to the number of connected neurons.
Here are a few more for you to research
a fortune cookie short of a Chinese dinner
a fried chicken short of a church picnic
a little light in the belfry
a pepperoni short of a pizza
a photographic memory but with the lens cover glued on
a sandwich short of a picnic
a trifle short of custard
about as bright as a burnt out 20 watt light bulb.
about as useful as a chocolate fireguard
Choose the one that confuses you the least.