Improvisation

[Dyvid]

The problem comes down to risk vs reward.
You are asking the player to stand still with no actions for 10s so you need to reward that.
MCH Flamethrower should be meaningful reward as in higher DPS and building up to something.
As for DNC, you have to stop DPSing for 10s so it needs a DPS buff for the party to make up for the loss. I've seen Healers pull DNC just to stop them from using the skill so they can focus on DPS.