Found something undocumented and unfortunately completely unexplainable right now. It's in, all of places, Keen Dreams.
When I was practicing the speedrun route, Apple Acres was a huge pain because I'd make it into the lower-left corner where you grab Boobus Bombs and then miss the jump to get the pogo. Sometimes I missed it a few times in a row, sometimes the cart would just kill me as I frantically hopped. Ironically enough, my current record makes a mistake earlier in the level and coincidentally synced up my jumping to the pole with the cart being a stepping stone to get to it, so I didn't have to worry about it then.
I looked into this discrepancy further, mostly because I'm confident I can grab a pole almost all of the time, even if it's invisible, and even if I can trouble with poles for other reasons. It turns out that, somehow, Keen's jump can get stunted. It's not a lot by any means (perhaps one or two pixels) but it's JUST enough to miss that pole, which is probably the only reason I'd ever notice it.
This are some details that I've tried to glean after trying things out in that little mine shaft, but please note that none of them are certain. I really wish they were, but I yet to consistently reproduce this bug. (Note I'm using shareware version 1.01, in case it was inexplicably fixed in other versions.)
- It seems to carry over until Keen is killed, similar to key storage. Meaning I could get this to happen, immediately reload, and then have it happen again regardless.
Keen doesn't stand at a different height when his jump is stunted.
It doesn't appear to have anything to do with horizontal momentum nullification when you're next to a sheer vertical edge (which you can amazingly pull off in that area, as small as it is.)
It doesn't appear to have to do with the cart. (I usually jumped over it pretty clearly in my testing.)
It doesn't appear to have to do with buffering jumps, or buffering a moving jump into a standing jump, or vice versa.
It doesn't appear to have to do with variable height jumps, although the gradation of jumps is small enough that it could be a really particular sweet spot.
It has nothing to do with the jump into the area beforehand. (I made a save specifically after the jump in case it could be isolated to strange pole behavior, since the fastest way to reach the area is by jumping off a pole.)
Steps to (maybe?) replicate:
1. Go to Apple Acres
2. Fall yourself into the lower-left area with the Boobus Bombs and the 1UP
3. Save at the very right side
4. Exit game, reload save (just to get rid of any weird memory floating around)
5. Make your way to the left, jump
from the ground into the flower pot and 1UP while grabbing for an invisible pole
6. If you grab the pole, reload and repeat step 5.
7. Keep trying until you never grab that pole.
The stunted jump is noticeable, too. A full-height jump from where the pole is will obstruct Keen's eyes at its apex; a stunted-height jump will not. Please let me know if someone can also make this happen and let me know I'm not crazy.
I honestly don't know if this would affect anything else: apparently you can just barely grab that pole and, since it's a pretty secret area and you don't have to grab it from the ground, I really doubt they were so lazy as to put a similar jump in the game (unless it also involves a cart). If anyone can make a custom map with a custom tile that has very obvious height markers, we could play around with this and figure out the cause.
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I actually have a third glitch that I just remembered, but I'm gonna hold off because triple-posting seems rude.