I've seen the video, and it WAS hacked for low gravity and invincibility. From what I can tell, at least.
And the difference in time from the "lives" screen before 1-1 and the time between grabbing the axe and Bowser hitting the lava to me seems about the same. And it was on an actual NES, about 6 months ago, so I have no tape of it... all I remember was that I grabbed NO power ups (Yes, I took the low road in 1-2 and went almost as fast as one would over the top.) and didn't die or stall at all pretty much. I've never been able to replicate it, either. Bah.
Stupid Quotes: (9th edition)
AP U.S. History teacher: "Your groups may have no more than 3 people in them."
*About one second later*
Tom G. (Student in this class): "Can we have 4 people in a group?"