Re: [math-fun] infinite comic strip proof of knot non-cancellation?

I'm worried about the validity of that proof. The issue I have is that perhaps this would "prove" that unknot+unknot does not equal unknot? See, if we had a finite sum of unknots, then they ought to be untangleable in a finite number of steps to make it obvious that the result is the unknot. But it perhaps is not obvious that an infinite sum can thus be untangled.