From:

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I said:

"Assuming we are counting quarter-twists."

I realize that there are people out there who like to count

half-twists as a single twist. I don't. I'm not trying to force my

way of counting twists on anyone. I always try to be carefull to make

this assumption explicit out of courtesy to those who might want to

count otherwise. (Sort of like the Axiom of Choice.)

In fact I DON'T know if that result is true if you count half-twists

as well. I suspect it is, but I don't have a proof.

You needn't jump up and down and point every time one of us

quarter-twisters reveals himself. This one, at least, is well aware

of his assumptions.