shuffle rock beat

[livewire80]

ive learned this beat as 1 _ a 2 _ a 3 _ a 4 etc on the hi hat or ride or whatever

If you play the shuffle rock feel with a little more advanced drumming, there are beats that land on the &'s which make it sound really cool. BUT do you play those beats on the &'s on the metronome click ( my met is set at 8th notes beats )or should they be played on the e. this might sound confusing but i tried explaining the best i can.

thanks for your help