It's seriously over-estimation. Esseless hard mode, like most of the other hard modes in this game (minus Lost Island) can easily be achieved with a 4-Man group as long as you pay a bit of attention to the mechanic.
If Headshot is interrupted, and if the missiles salvo is not hitting all the dps, there is a lot of room to do this Hard mode in Daily mods-gear, which is how it should be.
We've been 2-manning Esseless HM (with a mix of Columi/Rakata), and many others have. Asking for all encounters to be under-tuned will quickly make them boring and will eventually hurt the player base a lot, which we don't need.
That is simply not true. Even without the headshotz all his abilities hit for 6k+ on a geared tank. Fresh 50 tanks get GCDed.