I did a single-segment OoT run just today, which was a very entertaining experience. My time was 6 hours 49 minutes 9 seconds, which converts to roughly 5 hours 41 minutes in "real money". I stuck to TSA's 4h57m route extremely closely, skipping the Lens Of Truth and all those other groovy skippable items.

I got up at around 9am - which is stupidly early compared to how late I've been sleeping in lately - and did the run between breakfast and dinner, lunching on some ready-placed bananas. I felt ill and tired through young Link's section, but perked up later. I drafted a friend to occasionally hit A through dialogue while I used the loo.

The time I got sucked. There were huge, huge errors. I was talking to my friend too much during the Fire Temple and just kept making silly mistakes, and missed Volvagia once which cost time, but the first real slip-up was the fact that I DIED at Phantom Ganon. I loathe and despise Phantom Ganon and always have, in fact; sometimes you can absolutely destroy him in three fireballs, but other times you just forget the rhythm and die horribly, like I did. Urgh. Then I utterly mucked up the block-pushing puzzle in the Ice Cavern, and falling into the chasm twice. It took me eight or so attempts to cross the Haunted Wasteland, because I hadn't learned the route adequately. I forgot to get Din's Fire before beginning on the young Link part of the Spirit Temple, and had to backtrack for it. I ran out of magic to cast Din's Fire and enter the Shadow Temple. And I died again at Twinrova. And those are just the BIG errors. In terms of general pace, I think I was running slower than TSA, which is to be expected, as he is better at this game than I am.

Changes I would make next time and advice I would give to others looking to attempt similar feats would be:

1. Have your route written out in front of you and available to refer to when you need it. You ARE going to forget where you're going at some point. Or forget the optimal solution to some puzzle. Or warp to the wrong place.
2. OoT is a long game and you are going to have no choice but to eat at least one meal while playing. I suggest picking lunch, playing from after your breakfast to before your dinner. Packing lunch is easy, and there are copious cutscenes you can eat during, even with one hand.
3. Try not to drink too much while playing. Even so, you will be using the toilet during the game. Unless your N64 cable is long enough that you can play while on the loo - which has been done - you will find yourself leaving the game unattended to do this. There are plenty of long talky bits but very few actual, non-interactive cutscenes. You can do what I did and get someone to tap A for you in your absence, but I don't know how the various videogame scorekeepers will look at this.