In theory, yes.
In reality, it's different. Because Refresh is not primarily an agro drop, but a Mana regen for the party (or milking an extra tick of Foe Requiem). You don't use it on cooldown for agro, it's situational.
I can agree on tactician because TP regen is not useful in raid context most of the time. So that halves agro once every 180sec.
But second thing, Bard and Machinist DPS output is not linear but very bursty. Say a MCH had high agro, uses its Tactician, Refresh being already used ; each 60sec MCH can rip agro in its Wildfire 10sec window, or build just as much as the amount that was dropped just before. And it's the same for a Bard's Wanderer Menuet, though potencies and duration change slightly, but then you have Crit procs and raid buffs coordination that can change the figures.
For casters it's roughly the same, but Diversion is far more efficient since it has been buffed. You can use it on cooldown (as long as you benefit from its whole duration) and never have to worry that much about Tank enmity nor sacrificing a Lucid dreaming for agro when you might need that MP regen later (RDM especially)
@Shurrikhan TP MP Agro ae not designed to rely on these actions, I agree. But it's much more to be considered that it was during heavensward, because DPS output and uptime have exponetially increased. We have stronger tools now and they work fine, but not for a few jobs, which is what I'm adressing right now.
A bard bursting in Wanderer Menuet in Heavensward is nothing compared to a Bard with consistent full Pitch Perfects, Refulgent Arrows and oGCD used with no clipping, on cooldown, buffed by the holy crit Meta.