Wtf, hax. This changes everything.
I'm reading that you could do this in the first game, too. I completely cleared that game back when as well, and it never even occurred to me to try that.
Edit: Well, kiddos. I got to the part where it turns out doing this is mandatory. No spoilers, but I'm sure some of you know which part. I guess the bit right before that is what teaches you this, but I use the term "teaching" as loosely as possible. Still and all, knowing this several hours of gameplay earlier would have possibly saved me from several embarrassing perforations due to jumps fallen short.
Haven't played Silksong yet, but you could absolutely do this in the first game. You could bypass a few rooms that were supposed to be off limits until much later if you were good enough
That's what I've read now that I've gone and checked the internet. It honestly never occurred to me to even try up until now.