This trick skips both Small Keys in Skyview Temple, and therefore two-thirds of the dungeon.
When you enter Skyview Temple, save at the first statue, then activate BiT, either via a corrupt file or dying to the Keese. BiTWarp at the Upper Academy Statue, and you should appear in the circular room at the center of Skyview. The room will be only partially loaded.
To reload the room, go to the room with the Boss Key and follow the path on the right, entering the door when you reach the end. Kill the Staldra to unlock the door and go back the way you came to reload the main room. From here you can either go directly to the Boss Key or go back through the gate and obtain the Beetle.
This same BiTWarp is used during the second visit to Skyview. For that visit, you can activate BiT using bombs, then after the warp, reload the room by saving at the nearby statue and either deathwarping or reloading your file. You can then proceed to the triple Stalfos fight.
If you perform the BiTWarp above, you'll reach a Skulltula blocking a jump over a pit. To pass the Skulltula without the Beetle, you can use a horizontal Skyward Strike to cause the spider to swing like a pendulum, and jump past it with good timing.
This method is the most consistent method for handling the Stalfos, but it requires a shield.
As an additional small timesaver after the Stalfos dies but before the chest spawns, if you aim the camera 45 degrees left of where the Beetle chest will spawn, you'll skip a small camera panning cutscene after the chest spawns.
Instead of climbing the vine wall and having to recross the tight rope, jump back to the vine you previously used. If you are low enough on the vine and gain enough speed, you can reach the second vine and then jump over to the Boss Door.
In the first phase, you must move Ghirahim's hand to one side, then attack from the other once he locks his hand in place. You can hit him three times before he will begin to dodge again. One recommended method is:
Ghirahim's second phase is slightly random, as he has four possible attacks. In general, you want to wait for him to be vulnerable, then attack in a specific pattern. It is possible to finish Ghirahim's second phase in six cycles:
It is important to slash first before spin attacking, as Ghirahim takes more damage when stunned. If the stab in the first cycle doesn't land, or you use a different combo, it will take seven cycles to defeat Ghirahim.
These are the attacks that Ghirahim uses:
In this attack, Ghirahim will hold his sword in a guard position for a second or two, then attack. This is the easiest attack to deal with, as he is vulnerable immediately.
In this attack, Ghirahim will disappear, and then reappear either in front of or behind you, with his sword held in a guard position. He is vulnerable immediately after reappearing.
In this attack, Ghirahim will hold his sword behind him to either side (sometimes hopping backwards first to gain distance), and then charge you. He is vulnerable while charging, but you have to time the slash carefully. As a safer alternative, you can spin attack, but you'll lose the chance at a six-cycle fight. As an even safer alternative, you can shield bash this dash attack.
In this attack, Ghirahim will summon five red daggers in a line and fling them at you. This is the worst attack to get, as he is never vulnerable during it. The fastest way to deal with this is to swing your sword to hit all five darts, thus cancelling the attack.
You want to get as few dart attacks as possible, and cancel those you do get as quickly as possible. One good strategy is to not Z-target until he is vulnerable, and to try to herd him towards the center of the room. This will minimize dart attacks and avoid him teleporting away from you when he reaches the edge of the arena.
To defeat the Bokoblin Archers guarding the tightrope in front of the boss door, it is normally required to use the Beetle to drop a bomb on the archers. However, this can be skipped by using the upgraded Hero Mode Skyward Strike to hit the Bokoblin Archers from the other side of the rope. With a good angle, you can hit both archers in a single Skyward Strike. A good way to get the angle required is to stand in the right corner of the platform near the rope, and aim for the left edge of the boss door.
There is a quick method for killing all three Stalfos at once using bombs and Skyward Strikes. Follow these steps:
You can speed up the above a little by throwing the second bomb in between the first Skyward Strike and the first spin attack, but the timing becomes tighter. If one of the Stalfos survives the second round, just finish it off normally.
These are all strategies and tricks that are either not used in a current route, or not useful in a speedrun setting.
By running next to the spiders on the bridge, you're able to jump past them, which allows you to skip the vines in the room.
After you do the BiTWarp to the central room and reload it by killing the Hydra, it is possible to finish the dungeon without getting the Beetle. This quickly leads to a dead end, as you need the Beetle in Earth Temple.
In the eastern water room, you can skip the Mogma text near the web by running up the wall next to the first blue mushroom on the right. After getting the key, retrace your steps back through the watery crawlspace and spin jump up to the ledge on the left to skip the text on the way out.
Skyview Zero is the state that Skyview Temple is in before you hit the switch outside the temple to open the main door. Many parts of the temple are unloaded, including most doors, making the temple difficult to navigate.
Save at a statue in the Deep Woods and activate BiT. Perform a BiTWarp at the Lower Academy statue; the positioning here is important, as the wrong position will lead to an infinite voiding loop. One position that works is standing next to the statue on the left side.
Once you've done the BiTWarp, you'll end up behind Skyview Temple. The walls here aren't solid, so you can run to the stairs leading into Skyview and jump into them from behind. Walk up the stairs to the loading zone and you'll enter Skyview Zero.
Since most doors are unloaded, it is very difficult to do anything useful in Skyview Zero. One thing you can do is obtain the Dungeon Map; this is the same dungeon map as the other two versions of Skyview. It's even possible to do this without the slingshot, as the slingshot switches can also be activated with the sword.
You can also do the same BiTWarp as the other versions of Skyview to reach the central room. You can enter the Beetle room, but the Stalfos fight will not trigger, trapping you there. You cannot reach the Boss Room, as the tightrope doesn't load.