d: "A real sprinter is likely to be running these at intensive tempo pace (80-90%), because he would know better than to go over 95 percent"
Exactly.
However, the alleged person is a "detrained" sprinter. When you "detrain", you lose capacity. After the first or 2nd 50, if somebody went that hard, they would be cooked, if they'd had no rest. I know, I have done it. On the following ones one just isn't able to go that "hard", because one has depleted the energy reserves, and then one is relying on a different energy system, one "designed" for that kind of work, one that enables that kind of work.
For me, it's not that I've never trained "hard" enough to puke, it's that I've never trained "stupid" enough to puke. If you are, you're an idiot and training wrong. Before short sprint stuff, I have always had a good meal, solid. NEVER when doing short-to-medium work should you puke, EVER, or you're an idiot and working the wrong energy system.
And when doing longer stuff (200-400) sure you can puke, but I never did these workouts with any food freshly in my gut, except for maybe some baking soda and water.
In any case, this alleged guy is reported as being an ex-sprinter. Sorry, but no sprinter I have ever known, and I have known lots, would puke in this type of situation without stomach flu or food poisoning--or if he or she had had a few drinks prior to doing this type of bogus workout-with-a-friend, not a real workout. I still don't buy it.
Like d said, no "sprinter" would do these at 95%. Believe me, if this person is real and actually was a 10.9 guy, he would blow your doors off going at 60-75%. I'm not kidding.
And why do I care so much? Well, because it's sprinting, of course!