Thank you. Now I know why you do (although I kind of figured…).
I had the same kasha about how preventing creases is considered a tikun (although, the isssur is actualy nireh kimisaken, which might be easier.)
His point about the “yesh mi shomer” I can understand, although I would think it does imply a machlokes. The Shach he mentioned is the Rema’s comment on the S.A., not the mechaber himself; to argue on the Machtzis Hashehel and M”B, he would need a raya from the mechaber alein. I do find it odd though, to say that the mechaber sides with the first shittah when he explicitly says “v’nirin d’vorov” o the second shittah.
He also doesn’t deal with the hachono issue (unless I missed it?).
I suppose you could say that the same way there’s no hachono issue, according to the second shittah, when the foldiing is not on the creases, there is also no hachono with today’s changed metzius. The Aruch Hashulchan doesn’t seem to do this though, since he needs to go with the Rishonim who don’t hold of it at all.