if you want to beat Mipha it is required anyway, it's really hard to get to the 40:30 - 41:00 mins mark without it enough already, but i still believe sub 40 is possible, but ofc need perfect execution of this among other tricks
what, looks more like a whole minute or a bit more
Pigjump is done in the Pigline level. Instead of opening the door with the button, you just go to the right right away and climb the ladder. Go all the way to the control room where the pig is patrolling, and there you have to wait for it to get to a specific spot, then you have to jump on its head and jump again to the control panels. You can then start sabotaging it and once it's done, you just walk back and get yourself killed by the pig to get out of the room. You will be respawned at the door with the button, you just press it and you can go on, this level is done.
Be aware that the pig can be what they call "slippery" and it affects the whole run, that means you will get through it as if it's not physical anymore, if it happens, your pigjump run is over. ALSO DO NOT PRESS THE BUTTON FOR THE DOOR, ONLY WHEN YOU SABOTAGED.
The rules have been updated for Glitchless.