Quote Originally Posted by challenger
Only adjectives can be "substantive," and gerunds are verbal adjectives.
В русском языке есть словосочетание "отглагольное существительное", т.е. "verbal substantive".

Quote Originally Posted by challenger
But as for the other, how do I know when it's alright to use то, чтобы + inf and when it isn't?
I think it depends on the context. Show me some examples.

P.S.
"исключая плавание в голом виде" = "за исключением того, чтобы плавать в голом виде."
It has the same sense.