About Sonic the Hedgehog 3

How is it that Tails is punishing difficulty at the Act 2 boss? The player in this video is not freaky good (lots of mistakes) but he gets it on one try. The vid even shows how Tails can damage Dr. Robotnik's machine simply by rubbing his spinning tale against it (while the machine's blades are stationary).

Skip to the battle at 8:20
I had no problem myself getting past it when I played all the way tales through Sonic 3+Knuckles (Real machine, no emu cheats, no game genie).