An addendum to mzxrules' post above, here's a list answering almost any possible questions:
- After leaving the Kokiri Forest shop, the TAS jumpslashes into the water and flies backwards.
>>> There are four ways to escape Kokiri Forest before completing the Deku Tree. This method is called “Water Extended Super Slide” (or Infinite Super Slide, whichever you prefer). By entering and exiting the water quickly while holding the control stick a specific direction, you can move like this. This gives enough speed to be able to clip the Kokiri blocking your way out of the forest.
>>> This method of escape is considered unoptimal for a TAS because it activates the “get Fairy Ocarina” cutscene. This is unnecessary and only wastes time, as through another glitch known as Ocarina Items you can play an Ocarina even though you have none.
- After going into Hyrule Field for the first time, the TAS switches between the Sword and the Deku Stick really fast.
>>> Switching between a Sword and the Deku Stick every other frame skips your encounter with Kaepora Gaebora, an owl who talks to you and wastes time.
- After skipping the owl, the TAS flies backwards.
>>> This is a Super Slide. By rolling into something you can grab and having something push you away from it, you’ll fly straight backwards as long as you hold the R button.
>>> >>> Later on in the run, the TAS is able to move in different directions after a Super Slide. This is an extension of the Super Slide called the Extended Super Slide (or, again, Infinite Super Slide). The same specific direction on the control stick is held to achieve this as it was during a Water Extended Super Slide.
- In the Fishing Pond, the TAS receives the Golden Scale as a child.
>>> By holding the Z button as you come out of the water and holding until you talk to the fisherman, he’ll give you the Golden Scale for some reason.
- The purpose of the trip to King Zora in Zora's Domain is only to get Ruto’s Letter out of the Bottle so that you can use it. This could be considered unoptimal because you can get a Bottle another way.
- Before taking the owl to the entrance to Hyrule Castle Town Market, TAS messes around.
>>> This is to wait until the sun rises and the bridge to the market is down.
- Going out of bounds in the Temple of Time is used to skip getting all three Spiritual Stones.
- Once you become an adult and talk to Sheik, the TAS goes out of bounds and dies.
>>> After the adult sequence, you’re stuck in that room because the Door of Time blocks your way out (you never opened it). You need to get out of bounds by clipping into a pillar and die, save, not continue, then resume your save. You’ll appear in the Temple of Time normally and be able to continue.
- Why is there a Bomb icon on C-Down? He never picked it up…?
>>> This is the way the game was developed. As Adult Link cannot use some of Child Link items, the developers added a default C-button setup (including Bombs on C-Down) for Adult Link.
- The TAS gets the Pocket Egg before going to the Graveyard to give it time to hatch (it needs one full day).
- The TAS goes into the Graveyard and races Dampe for the Hookshot.
>>> This is considered unoptimal because the newest route skips the Hookshot. The Hookshot was only necessary in two places:
>>> >>> Getting into the Fishing Pond. This is skipped by obtaining a Magic Bean through another sequence break, planting it, and riding the Magic Leaf as an adult to the Fishing Pond.
>>> >>> Crossing the broken bridge in Gerudo Valley. This is skipped by another glitch which would allow you to cross the bridge.
- After getting the Hookshot, the TAS dies.
>>> After the Hookshot room, the player needs to play the Song of Time to progress, which was never obtained. Therefore, the player needs to get either crushed by the door or hop back into the Hookshot room once it closes to get back to the beginning of the race.
- The TAS pulls out the Ocarina of Time despite never obtaining it…?
>>> Adult Link will always pull out the Ocarina of Time, even if he has the Fairy Ocarina instead.
- The TAS goes into the Fishing Pond and out again after stealing the fisherman’s hat!
>>> Stealing the fisherman's hat was not necessary; it was only done for entertainment (no time was lost doing so, however). This was part of a glitch called "Steal the Fishing Rod". By diving in shallow water and casting the rod immediately after surfacing (the TAS directs the cast towards the hat so he can steal that too), you can take the Fishing Rod out of the Fishing Pond (usually the fisherman stops you from doing so). By getting the Fishing Rod outside, you can get a Deku Stick on B, which allows you to get a Bottle on B.
>>> The Fishing Rod stays on B until he gets to Kakariko Village.
- The TAS pauses and unpauses, then releases bugs in a Bottle multiple times. What’s with this?
>>> The pause and unpause turns the Fishing Rod into a Deku Stick
>>> The “error” sound played is the process of putting a Bottle on B; you get a Bottle in your hands, hit the C-button the Bottle is on then hit B to turn it into a Bottle, all in mid-air. This begins Reverse Bottle Adventure (RBA). The item on C-Right when the bottle is emptied or items are picked up in the Bottle on B manipulates the memory in various ways.
>>> The first bottle dump, with a Bomb on C-Right, activates the slot where Bombs would be in your inventory and bombs will appear if you destroy bushes ("bomb drops").
>>> The second bottle dump, with the white chicken Pocket Cucco on C-Right, gives Link a pair of Gauntlets that allows him to pick up bushes and get items from them. This is necessary because Link currently has no weapon equipped to cut the bushes himself (the Bottle is on B)
>>> The third bottle dump, with the blue chicken Cojiro on C-Right, gives Link a Quiver and a Bomb Bag so Link can collect bombs.
>>> Later on in the run, the fourth bottle dump, with the Poacher’s Saw on C-Right, gives Link various songs, including the Prelude of Light song, so he can easily go back to the Temple of Time, and Zelda’s Lullaby, so he can summon the Great Fairy and obtain Magic.
>>> Later on in the run, the fifth bottle dump, with the Broken Goron’s Sword, gives Link various Medallions, including the Spirit and Shadow Medallions. This allows the cutscenes where Sheik reveals his true form and the rainbow bridge to Ganon's Castle is formed to be triggered. For some reason, the only check to activate these scenes the developers programmed into the game was for the Spirit and Shadow Medallions.
- On the bridge where you received the Fairy Ocarina, the TAS sets a Bomb down and does a little jump on the side of the entrance to damage boost onto the sides of the bridge, saving some walking time.
- The TAS is able to buy an Arrow because he got the Quiver via RBA earlier.
- Directly after this, the TAS jumps directly onto the roof of a building. The fact that this roof is able to be grabbed is just a fault of the game design.
- Why does the TAS pull out the Odd Mushroom twice in the Old Hag’s shop?
>>> This is also a result of the game itself. The first you pull it out the game will never recognize it.
- In the Great Fairy’s Fountain, Link plays the Ocarina with the Hookshot…?
>>> This is a glitch called Ocarina Items which would allow the Ocarina to be skipped. To do this glitch, you need to have a bottle in your hands, jump or backflip, and then press the button the bottle was on followed by an item while in mid-air.
- Just a note, the TAS uses a slow console-speedrun setup to get across the broken bridge in Gerudo Valley. It shouldn’t be possible to cross without the Longshot (obtained in the Water Temple), but the Hookshot can reached with extreme precision.
>>> It is possible to cross the bridge without the Hookshot, as mentioned before, with another glitch.
- The TAS skips dispelling each barrier in Ganon's Castle by hovering with bombs?
>>> Briefly, a glitch called the Infinite Sword Glitch allows Link to hover by blocking damage from bombs in the air.
>>> The way the game is programmed, the trigger to enter the interior of Ganon’s Tower is accessible by just flipping into the side of the wall.
- The TAS uses the Master Sword to defeat Ganon even though it was knocked from his hands?
>>> The player is able to keep the Master Sword if he performs and sustains a Super Slide during that cutscene.
EDIT: Minor spelling fixes.