The beat the song is built on is one bar, played through bars 5-7, 15-20 and 24-26, and 3 more places -- 67.9% of every bar the kit plays. Learn that one and the song is very nearly finished.
It is played on hi-hat, snare and kick, counted in sixteenth notes. On its own it scores 68 out of 100 -- demanding -- and the thing that decides that is how many notes a second it asks for.
The whole song is 74 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 62 BPM -- and adds the notes back over 4 rungs, each with a tempo to reach and a gate to pass before the next.
Tempo goes 62, 73, 84 and 95 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 4/4 at 95 BPM, counted in sixteenth notes. It is written out above, and it covers 67.9% of the bars the kit plays.
Bars 5-7, 15-20, 24-26 and 33-44, and 2 more places. The time is kept on the snare to start with, and it changes 1 time over the song.
68 out of 100 on its own -- demanding. The song as a whole is 74 out of 100: demanding, mostly on the independence between the hands and the feet.