Entity encounter is silly.
Talking about what tactic is proper is silly also.
To kill projection there is no need to have more than 5 melee classes each, so 10 in total for raid. If for whole instance t4 you like to have 6 soldiers, and next two are healers for projections (bs probably) it leves in raid only 2 melee spots left among sin, barbs and hoxes.
Using melee characters who are not needed on projections to dps Entity with xbow is silly.
Not bringing more than 2 melee dpsers to raid because there is no place for them in raid is silly.
Switching even one melee toon to range is as much 'abusing mechanic' as switching 8.