Like this -
H = hi hat
S = snare
K = kick drums
S S S | SSSSS | S S S | S S S |
Like, the snares are not even.
It doesn't require the same independence as polyrhythms - it's just off-beatness. It's harder than ordinary, but NOTHING compared to polyrhythms! You try right now - do this;
In the same space of time (or same length measure)
Tap you finger 5 times
Your other finger 7 times
and your foot 4 times
It's freaking hard. I don't understand how ANYONE does it. It's just insane. IMO one of the greatest musical abilities.