If Red Mage ever gets a DoT it would likely be attached to their finisher as the balanced mana option to VerFlare/Holy, or added as VerAero/Thunder alternatives with equivalent potency. Either way it wouldn’t be a 100% uptime thing. The only useful purpose a DoT could serve within RDM’s rotation is as a way to delay or manipulate B/W mana generation or procs. I could see other options for mana generation but that’s the reason I would add one at all.