A friend of mine, Crazy1993 recently submitted a 1:17 in Sonic's Speed Highway. This wouldn't normally be cause for speculation, except for these things:
1. He isn't the best SA speedrunner.
2. He claims to have done his run on a PC using a keyboard.
3. He also says he did not use any shortcuts.
4. He didn't have any version of the game at the time he supposedly got the stat.
5. I know him well, and he is clearly making this up.
He later tried to revoke his claim by saying he "misread" it, that he actually got 2:17, but the other problems persist.
Remember, it's not really possible to sub 2:30 (or with his skill, 3:00 or 4:00) without shortcuts.