An interesting article about how the memes and systems from MMOs are permeating other kinds of games. In particular, the “Holy Trinity” of “tank/DPS/heal” is invoked once more. It’s even applied to real life work situations.
I know that I’ve had good line managers who ‘tanked’ senior management so that the dev team could get on with finishing their project on time. How does it fit into single player games? Well, the metaphor is so pervasive that it’s easy to feel that you just tanked a level or that some NPC is your personal support class even when there’s no tanking or healing involved at all.
Our design team certainly has a tank to take damage from the higher-up bosses at work, and I don’t know if I fill a DPS role or healing role when it’s time to help him out. Maybe I’m a Druid and do a little of both. Don’t forget Crowd Control! CC is not part of the “holy trinity,” but it’s good to have when the meeting gets too big.

The Holy Trinity doesn’t include CC or buffing, because WoW doesn’t have those roles.
Everquest sure did though, they were vital. (says the former bard who filled both of those roles, most of the time simultaneously)
The Minstrel in DAoC filled three of them (DPS, CC, and buffing), as well as a fourth in stealther, but that was primarily PvP, and was only generally useful as a soloist.