If anything, you've got it the wrong way round: Regen on the tank helps to keep them healed up without burning through your MP (Regen+Cure on recharge is roughly comparable to Cure II on recharge but a lot cheaper), whereas Regen on DPS will quite often end up overhealing them (unless they're still being targeted) when a Cure would have done the job. Regen on the tank also makes it safer to divert your attention to the other party members for a few seconds.