The beat the song is built on is one bar, played through bars 2, 36-38 and 40-41, and 15 more places -- 29.6% of every bar the kit plays. That is the spine of it; everything else is what happens around it.
It is played on hi-hat, snare and kick, counted in sixteenth notes. On its own it scores 74 out of 100 -- demanding -- and the thing that decides that is how many notes a second it asks for.
The whole song is 80 out of 100, so the beat is most of what the song asks for. Get it clean and the rest follows.
A part this hard is not learned by playing it slowly and hoping. The room opens it on its simplest reduction -- the timekeeper alone, at 80 BPM -- and adds the notes back over 5 rungs, each with a tempo to reach and a gate to pass before the next.
Tempo goes 80, 96, 112, 129 and 145 BPM, and the gate at each one is 8 loops in a row with no wrong note and no wobble in the time.
PRACTISE THIS BEAT →A one-bar groove on hi-hat, snare and kick, in 3/4 at 145 BPM, counted in sixteenth notes. It is written out above, and it covers 29.6% of the bars the kit plays.
Bars 2, 36-38, 40-41 and 44-46, and 14 more places. The time is kept on the hi-hat to start with, and it changes 28 times over the song.
74 out of 100 on its own -- demanding. The song as a whole is 80 out of 100. Hard, and what makes it hard is the independence between the hands and the feet.