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.
I'm surprised that you wouldn't know this having played the first game, because I remember it being required to reach certain places. Maybe it wasn't ordinary spikes ? or maybe it was only in the White Palace ? I can't remember
Well, there are the specific pogo targets in various places which are spiky presumably to punish players who are bad at pogo jumps. Silly me, I figured those were their own thing and related to the other various pogo targets (like the ones that explode shortly after you hit them, or the punching bag ones that swing away after the first hit) and not the ordinary spikes that festoon every goddamn available surface throughout the rest of the games.
I don't recall any spike-floor pogos being necessary in the first game, but I can sure see how they'd allow you to make some areas easier or enable sequence breaking.