First of all, let's get real for a moment. I normally like to think in terms of humans. We know what we are capable of, so let's cut some crap out, alright?
First off, sure, real endurances have no Pause button. Sure, real endurances can go for more than 2 hours. But if you ask me, I don't know one person that can sit down and play a game for hours on end. Meaning, not interrupted, not having to go to the bathroom, not answering the phone, that sort of thing. There was someone I once talked to 2 or 3 years ago at K-Mart about Gran Turismo 3. The clerk at the Electronics section said that he couldn't do those long races. I told him that the Tokyo endurance takes up at most 3 hours. So what, is this guy a wimp for not doing long races? Well answer me this. How many people actually have enough time to run a very long race, even if it is pink-colored Toyota Vitzes running around Test Course for 10 laps? Not many. People often shy away from longer races. We could deal with Gran Turismo 2's 5-lap races, but GT3 makes the races longer and harder, and you'll most likely had to make a pit stop. The PD Cup for GT4 was all Reverse courses lasting about maybe 40 minutes (I have only played the Tokyo race, and I'm saving the other rounds until I complete most of the other races first). So, if you can do races longer than normal, that's fine. If races are too long, we have a problem. Can you maximize your time to playing the game? I know I can. If I have time on my hands, I'll race a decent-sized endurance. If not, I want to back out until I DO have enough time.
Bottom line- not everyone can run the longest of races. As a game company, you want to please EVERYONE. About one time where I needed to burn up as much time as possible was in the Nintendo 64 game "Star Wars: Shadows of the Empire." Playing that stage where I had to beat Bobba Fett took almost half an hour. Didn't mean the other stages were endurances. But, can the "no pause, no save" for the "make all races 500 laps" crap. Be humanistic. Be real. Be careful... have a good night!