[Continued thematically from here (maybe - in all the excitement, I kinda lost count of it myself)]
I handed George the very famous puzzle and asked him if he knew how to solve it.
"Oh, yes, of course. You insult me. I even have a mnemonic of sorts."
He explained the co-ordinate system that used vowels going down and consonants going across and a couple of the specific moves (like M was "move together" and S was "side-step"). Then he said in a sing song voice as he solved the puzzled:
"I FED the CIRcus some DAM GAS *rotate*
CIRcus DAM GAS *rotate*
CIRcus DAM GAS *rotate*
CIRcus DAM GAS"
"What happens to the co-ordinates when you rotate?" I asked
"Oh, they stay in the same place, so they refer to different parts of the puzzle. Anyway, don't interrupt. I'm almost done now. So, now you *singing again* GO all the way around using FODder from your HOLdall."
"But it's not finished," I pointed out.
"Oh, but it's easy from here. Just FIM and you're done!"
"Very good. That's very easy to remember. Did you invent the mnemonic?"
"No, it's a standard notation invented by David whatzizname. I just applied it to my favorite solution."
What puzzle did I give George, and what solution did he remember with the mnemonic? And what is David's name?