Actually, not that unbelievable. You could fairly easily skip from world 1 to world 8 quickly through the use of warp zones. I’ve done it myself. Never beat the game, but played level 8 quite a few times.
Well, I can’t get the video to work, but it’s pretty clear how he would have done it. World 1-1, 1-2, 1-3 getting the warp whistle, then World 1 Fortress getting the warp whistle. Warp twice to World 8, then run through all the levels.
Mario 3 had some extremely short levels. Some of them you can just fly over. This claim of 11 minutes, while taking some serious skill, is definitely believable.
Now, people have told me they’ve beaten Ocarina of Time in 5 hours. That I’d have to see to believe.
You should watch the video. It’s actually quite unbelievable. I’ve not done any reading on the matter but I am quite convinced (having played a LOT of mario 3 myself) that this was not done on an actual NES console. I would guess it was done on an emulator with a save/restore state feature. Just IMHO.
Oh, and here is a direct link to the video. I could only get it to work by clicking “Save Target as…”
Okay, having watched the video, I take back what I said. This is not something anyone could do with just practice.
Finishing the game in 11 minutes is nowhere near the most impressive thing in the video. So many of those jumps are just too perfect.
Oh, man. Oh, man. I am beyond impressed. And jealous, too. You know how long it took me to get passed those flying thingies? And I thought I was clever cause I knew the “dive off the boat and swim under em” trick.
Holy freaking whoever! I can’t imagine how long it’s taken him to do that. I’m correct in seeing he never got hit once, right?
I like games but I’ve definately got a line out where I say ah screw it. I’m not sure this guy has one.
I’m confused, what’s the big deal?
Mario Bros 3 is easy - the second flying thing on world 8 can be a pain but it’s not a hard game.
Can’t access the video as at work (boo) but not getting hit once does sound impressive.
That one isn’t the big deal. I have a video of a dude completeing every leverl, sometimes in under 11 seconds, entirely while small (except when he has to get big, which he does, for just what he needs to do that for, then immediatly gets small again). It was pretty cool.
But not as good as the SMB 1 bug exploit video.
He also racked up … what? 20 or 30 extra lives in those eleven minutes by precise jumping on cannon shots.
I never say this, but: OMFG.
You need to see it. To me, the first proper level (not one of the forced scrolling cannon levels) in World 8 was the most impressive.
The jumping was amazing. He finished with 99 lives, mostly from the cannon levels. And I considered myself a Mario nerd, but I never knew about the first whistle he gets, the walk-through-the-wall thing he does on the last level, or the fact that you can kill Bowser by jumping on him enough times.
SMB1 bug exploit video??? Never heard of it.
What’s that?
What does that show?
He was shooting fireballs at Bowser the whole time. The jumping was done so he could stay in constant close range and machine gun Bowser to death.
Oh. Well, I didn’t know that you could kill him that way, either. 
And I wanna know about that SMB1 bug video, too.
I’ve thought it through, and I think you’re right. However, instead of the save/restore feature, I think the thing that made it all possible was the “play at 1/16th speed” feature. Still darn impressive even if that’s how it was done, but I think I can fathom it.
There’s also a Metroid Prime speed run in which the game is completed in an hour and a half. If you have an hour and a half to spare, these videos (it’s split up into 15 different files) are very interesting to watch (and of course, it helps if you’ve played through Metroid Prime).
I can’t seem to load the video from any of the links, even after doing ‘save target as’. Strange.
I couldn’t get the video either. File not found.
I’ve beaten Super Mario Brothers 3 in under 15 minutes. 11 minutes is impressive, but very believable.
Oh, and if I recall correctly it takes 20 fireballs to kill Bowser, but only 4 hammers.