Mages are currently able to activate the Pyromaniac talent, which grants 10% haste when you have DoTs on 3+ targets, without actually meeting the 3-target requirement.
To replicate, apply DoTs to 3 targets inside an instance, then leave the instance. Upon returning, any DoT will activate Pyromaniac. This persists until the original targets die or the caster does, so if you skip those targets after activating this bug, you can have it active for the entirety of a raid like Bastion of Twilight. This will most likely be even easier to activate in Firelands.