Example Video:

Forward: This level is really hard to do fast unless you memorize the layout. It only takes like 15 minutes of effort, so I really recommend memorizing it.

First part really requires no memorization, just fully charge your rolls and try to take a straight path down the mountain. (Why did pac climb the mountain in IRR if he's just gonna go back down in the next level?) You can extend your rev rolls in some areas by sliding onto ice at the end of your roll, as you'll keep the momentum. It can be extended even further by jumping off the ice as it's about to end. You can rev roll directly into the final pac-dot, don't get scared or you'll probably overcompensate and mess up.

On the hill with a free guy at the edge of it, run to the opposite side of the hill before you start charging your rev roll, or you'll take fall damage when you land.

Rev directly onto the falling platform if you're brave. Aim between the chest and crate as you're charging the roll so you don't have to curve and hit them when you actually reach that area.

Before the platforms made entirely of ice DO NOT GRAB THE CHECKPOINT AS SAFETY. You will collect it by rev rolling off the crate anyways.

Note: Sometimes the game messes up here and you can't control pac after you butt bounce. For that reason, I wait until I'm entirely over the trampoline before I butt bounce.

Use the blowing guy to boost over the pit.

Next up we have pussy ass bitch skip (usually known as PAB skip.) It's called this because if you don't go for it you're a pussy ass bitch.

How I get this consistent is I always start my first roll from the checkpoint, then go towards the left wall and wait for the ram to pass me before rolling slightly to the center.

Do another roll to get to the area in green. Dont go to the red area or you'll fall off the side.

Now for the actual roll. You need to aim to the right of it, then swing left into it and back right off before you hit the wall. (Best shown by video)

Now the inside area. I'll say it again, to go fast here consistently it MUST BE MEMORIZED.

For the first roll, let go of the analog stick so that when the camera shifts you don't die.

For the first boosted roll I like to aim 45 degrees downwards, then aim pac so that he stays in the center of the stage the whole fly (as the holes are on the side of the path)

The next blowing guy is not worth it, so I just roll past.

The next skip is a lot easier than it looks. Just hold down-left and you should make it every time.

For the next boosted roll, I tend to go in at a more shallow angle, so that when I'm pushed I'm going straight downwards. I try to aim pac so that he stays in the center of the corridor, but its definitely a wonky boost.

For the next boost, make sure you stop early or you'll land on the ice and miss the opportunity to roll into it.

I don't really have much advice for the last boost, I usually hold up and slightly right, but reaction time for what direction to hold really plays into this a lot. You'll get better at it with time.

Take the final chain AND DONT MASH JUMP OR IT SOFTLOCKS THE GAME.