another thing you can do for /assist is use mouse-mapping.

keyclone/setup/mouse-mapping

left-click in the "mouse action" area.. LBUTTON should appear
click in the "key" area.. and hit the key you've bound to /assist

hit '+'
hit 'ok'

now when you left click a target, you'll also be sending the /assist key (sometimes i have to click a 2nd time)... keeping all your clones on the same target