Good question. I think they were assuming that being able to use Takedown on a target with any hp% would make up some single target dmg.
It would have... but Explosive Probe + Cluster Bombs is just too much damage. Plus you don't need 4-pc pve set bonus to use Hybrid at all. No we don't want a nerf to Engineering talents but maybe a buff to Full Lethality sustained single target DPS instead.