Hate to be negative, but the 750bpm attempt was proved to be fake by Record Setter.
The ‘debunk’ video is here.
It’s a shame because it sounds like he has decent technique, not sure why he got so obsessed with the world record!
TBH, I think it sounds crap. Just a sloppy mess with no musical merit.
I once saw a 1600 bpm attempt which claimed to be legit:
Do they verify these things with ultra slow-mo cameras. Do cameras that can track that kind of speed exist (I know it can be calculated, can’t do it right now sorry :D)
I think the clock running in the background, metronome verification are ultra archaic methods.
What is the human limit anyway?
Needless to mention that anything beyond 240 bpm 16th notes doesn’t make any sense to me anymore from a musical point of view.
Yes I saw this one, I have a sneaking suspicion this might not be real! Ha!
There’s some ridiculous and obviously fake attempts on Record Setter, so I’m guessing very little research and verification is actually done. If 1600 was legitimate, then he’d be playing almost 107 notes a second… his arm would explode!
I think Troy is going to try and answer ‘what’s the human limit’ in the Science of Speed, so that should be interesting. The fastest recorded I believe is 24 notes a second from @milehighshred. Some other guy did a similar speed on this forum, can’t remember is name 
I think it is fair to assume that the human limit is close to what @TheCount and @milehighshred have shown on this forum, i.e. 24 nps or 16th notes at about 360.
Anything that is too far above that is clearly fake.
I certainly can’t move my arm any quicker than that, that’s all I have! Also I’d have no reason too, 24 is already faster than I’m ever likely to need in a musical context!
If that there was a chance of that, I would definitely tune in and watch these record ‘attemps’. I wonder how many of these guys would be willing to strap themselves in with a CTC magnet and see how awfully unsynchronised their playing is?
It’d certainly make it a bit more interesting. Thankfully the ‘fake bumblebee’ records seem to have died down a bit now. I’ve seen quite a few ridiculous attempts now, not sure why anyone thought it was worth their time to fake something like that!