Drew Weatherton | [TAS] Mario Kart 64 - RRy Hill Cut Continuum Illustration @weatherton | Uploaded 3 years ago | Updated 12 hours ago
There's been some debate over in the Mario Kart 64 community about whether to allow the new hill corner cutter (youtu.be/905pZqyCnjI) on Royal Raceway non-shortcut competition. Some people pointed to it being "binary" (you get it your you don't) others to one of the floor polygons being steep enough to be "slippery" (though still not a wall).

So, I took one approach (of many possible approaches) at the hill and with this nearly identical approach showed that this cut is not binary and both with and without bounces are effective, often equally so. In all three videos, I'm turning left, jump right as I get to the grass and, based on the frame spacing and angle I enter the grass end up being about as fast with and without bounces.

Regarding whether bounces should be allowed at all; they already are. The Mario Raceway fast-lap fastest ending is done using a bounce (Dan's current world record uses it youtu.be/p4tKQ9W3Xlk?t=28). Bounces have also been used in non-sc racing on the old double-shroom strategy on this very course and some have used it to clear the second large set of bumps on Wario Stadium. They're a built-in game mechanic that occur when you jump while encountering a sloped surface. I believe they're the reason we sometimes see exceptionally large jumps over the new Frappe Snowland corner cutter (though, in that context the bounce is not desirable as it's clearly slower there).

Regarding whether to allow driving on steep "slippery" floors. This is already done. You can't take the cave cut in DKJP without going over a steep, "slippery" floor and the very best cuts do so twice (and those even jump over a tumble polygon when done optimally). Slippery floors are also driven on when doing a transtyle on the beginning of Rainbow Road. These are simply normal floor polygons that have a Z normal lower than about 0.855. Nothing special, Moo Moo Farm has normal road polygons of this type on the sides as well.

Oh, also worth noting: on Jeff Gutierrez's 8/18/2004 Royal Raceway fastlap PR cut this very hill, going over the slippery polygon, getting a bounce and saving him time. The only difference is he used a mushroom and didn't hit R when he got the bounce (so he didn't clear the hill completely in his case): youtu.be/BW5E3cbozHg?t=42