Yeah, I mean - I don't see the issue with that, outside of the issue of the argument for doing it this way being really weak.
You're arguing, as I've shown, over amounts of enmity gain that are less than even the weakest attack from any DPS class going full tilt. +100, +200 - every basic skill from every Job beats these two numbers. It's not a notable gain, but it is a substantial loss of offensive potency. And that's basically the bottom line. It's for sure a personal preference choice in your suggestion and the other ones, but that personal preference is
1. Marginal hate gains that will have literally 0 impact on how long I need to use Grit
or
2. DPS gains by using my main dps off-gcd attacks after Grit has been dropped and Slashing debuff has been applied.
I personally think the cons of 1 are significant, where the cons of 2 are not, but meh. As long as you're not using Plunge to tank a boss at the far north of the map where it spawns, I ain't got anything negative to say about your choice outside of "I personally do not agree with that decision, but you are welcome to make it."
Nope, that was someone else.
Yes, it would be +270 enmity gain in the second GCD to do it that way, +540 overall gain before the end of the first Power Slash combo.
The thing is that the total enmity generated by the lesser rotation is:
(450 + 150 + 100 + 770 + 1650) * 2.7 = 8424
The modified would be 8424 + 540 = 8964 = +6% enmity generated in the first 4 GCDs.
AKA: Not a noteworthy gain. A gain, absolutely, but not a gain that I would sacrifice DPS for. Extra enmity frontloaded into Grit is good, but it's much more beneficial to do this by feeding a second Power Slash before dropping Grit than spending a Plunge on the pull. You absolutely /can/ use your other stuff in Grit to start, sure. It might not even be a loss, if you would end up seeing +1 of said skill in the fight over what the guy who holds them sees. However, Plunge still shouldn't be between Unmend and Hard Slash.
I'm not neglecting that time. I'm saying that time does not exist. There's no delay at all between Unmend and Hard Slash, GCD-wise. When the GCD is re-filled, you're hitting Hard Slash and you're within range of the boss. Always. I mean, I do that on PLD all the time (and admittedly have not tanked much on DRK recently) and Shield Lob > Fast Blade is identical to Unmend > Hard Slash.
Yup! And I agree with you. I think in even gear, you'd need so few additional PS out of Grit that it becomes a gain to drop after one initial combo, but I can't realistically test that with my current DRK.
I will point out a few things here:
1. DP is 150 potency, Plunge is 200.
2. DP is not a gap closer - it doesn't modify the pull in any notable way other than injecting additional potency.
3. DP is a magic attack. It gets no bonus from Storm's Eye or Dancing Edge. Plunge does.
Note that I never once said "do not use Dark Passenger on the pull" - it is significantly less of a loss to use that as an additional off-gcd Enmity boost in grit than to burn Plunge there.