Damn, this topic is laugh-a-minute!
Seriously, though guys, I know what you're talking about with the whole hour/one-and-a-half hour thing, but what you're talking about isn't what the study was about. The only way they get a time like that is like this:
1. Hard on
2. Smack! You're in.
3. Stopclock starts.
4. Smack! Smack! Smack! ...
5. Pop.
6. Stopclock stops.
When you're taking it slow, moving around lots, and generally not really going at it full steam, sure you can last an hour (but, you do take a short break at the half hour marks, right guys?). It isn't rocket science, you just need the discipline to slow down before you get to that point of no return. Also, you can probably get going again within a half hour, maybe less, if it's a really hot night. I once spent five hours like that, tallying up six orgasms for me (and probably one for her!).
I think they're defining sex in the strictest way possible.