. You just can't control the second player, just like how the AI has to control player two in Chaotix, Shadow the Hedgehog, and Sonic Advance 3 rankings.
Also there is still a Rivals 2 rule missing regarding not earning scores in Free Play mode. The level results screen doesn't show a score in free play, but the score counter runs in the background and will print records to the statistics screen regardless: without the AI rival there to impose a time limit, score spamming is possible.
Sonic 3 requires a rule regarding tricks that can be achieved in the PC version or Sonic Jam version but not the Genesis version or any emulation thereof. The first trick that comes to mind is going over the ceiling in Launch Base 2 Sonic or Tails in a spot that only works on the disc versions. The same rule should probably clarify that the converse is not
true: for example, the Marble Garden 2 horizontal wrap zip can't be done on PC or Saturn, but is allowed and can be done on the Genesis version. I believe SM explained this restriction in terms of the rarity of the disc versions...
...which brings up the interesting question of the newfound slight advantages given to the disc versions in certain bosses in Sonic 3D Blast. It's only a second in most cases, but Sonic 3D Blast boss levels have a much tighter time restriction for a good rank on TSC than time charts for most other games. Strangely enough, the disc versions have disadvantages in ring/score divisions. The rarity of the versions and great differences in Special Stages was the main reasoning behind not introducing Special Stage charts, but it's being allowed in Time divisions. Interpret that as you will.
Sort of rare cases that I never got around to bugging Zeupar to add are in Chaotix. Firstly, what is Special Stage 1, 2, 3, 4, 5, 6, 1-2 in game are labeled as Stage 0, 1, 2, 3, 4, 5, 6 in the Stage Select. Judging by some of the records, I'd say people have already submitted for the wrong stages. Another quirk is that activating the Stage Select also activates a free-movement mode when the game is paused. Moving while paused is already addressed, but while this mode is active, screen fades continue to happen while the game is paused. This allows you to cheat the timer in several stages, and since all of said stages are easily accessible from the title screen (Introduction and Isolated Island 1, 2, 3, and 4), I propose that the Stage Select cheat either be banned for these stages, or a rule be added about pausing during a screen fade.
Sonic Battle has a glitch involving the mission in Amy's story where using a special attack on Rouge ends the battle. You can end the battle, then load up Challenge Mode and keep that condition, allowing for a two-second finish and easy points. It does
score well enough for TSC records[/s], but you can score high A to low S rank[/s]. I brought this glitch up years ago and got no response, so I'm submitting all of my stats when I get home from classes and to hell with replaying the entire game due to my high scores all being under this glitch.
EDIT: Submitted, and I was severely underestimating the glitch. I got a few records with no effort.
I can't think of anything else off the top of my head, but I'm sure there's other quirks we just never fixed.