I'm a necro main and i wanted to see if this might work
1 healing druid
1 harriers might gen healing scourge (soul reaping/blood/scourge harrier gear and weapons dagger/focus axe/warhorn)
1 Cps warrior (both banners and FGJ or wild blow if cc needed)
that's might gen and healing from the scourge so 3 kinda works like 4 (2 healers 2 might gen)
then most people will wanna bring 2 chrono (for alacrity)
but that leaves room for 5 dps instead of only 4
yes you lose 150 power to 1 group but thats not a HUGE dps loss, minor if you can bring a whole dps to compensate for it.
NOTE: I have done raids with no chrono at all, and just by following fight mechanics (dodge, green circle) it's pretty easy to beat bosses without alacrity and firbrands can bring quickness.