Ok here is my idea, I've been at this for a while now and it has all but halted my leveling.

Main targets a player in the party > healer heals main's target > main goes back to original target

i was hoping this could all happen using 1 key ( different macros on main/healer obv. ). it seems this is impossible using focus, but maybe using target=mouseover and castsequence and /targetlasttarget this might be able to be done quickly without having to click around and again for repetitiveness, using only 1 key.

something like this for the main:

/target [target=mouseover]
/(some sort of delay? or blank click of same button here)
/targetlasttarget

meanwhile the healer uses:

/target Jaheed
/target focus
/(some sort of delay? or blank click of same button here, this is to counteract the delay lag )
/cast [target=targettarget,help,nodead,exists] Healing Wave; [target=target,help,nodead,exists] Healing Wave