TL;DR at the end.
DBM for FFXIV will happen, regardless of opinions, because someone will code it as soon as add-ons are available. So will a DPS meter, and so on and so forth. For all these, my opinion is invariably the same: a tool is neither good nor bad, it's what we make of it. Simply put, you can't judge an innate tool, but you can agree with what human beings do—or don't do— with it. And this is why I think, in the end, that all tools can be useful, but you have to use them in a sensible and enlightened way.
Speaking mostly as a raid leader.
Generally in MMO's, if someone doesn't wish to use a DBM-like add-on and manages to remember everything and never dies because of avoidable mechanics, then that's great, and I have no problem with it (I would actually admire and congratulate that person). If that person dies every single fight because she/he forgot something, then I'll certainly push that person to use a DBM. Simple as that. There's no dogma, but there's no reason why someone's failings should be overlooked when a) a solution exists and b) that person is dragging the team down. No "pro-dbm" dogma, no "anti-dbm" dogma. It goes true for every tool.
For DBM specifically in ARR, I'll say this. Fights in this game are incredibly scripted and predictable, and not memorising them by heart usually means you don't have the time to react (due to the server live-state aggravated by internet latency and server congestion). It's a memory game much more than a reaction game. And I, for one, don't like that; it flat out kills my enjoyment, because my 'fun' is to react well and improvise heroic moves in dire situations, certainly not to learn fights by heart—didn't like learning poetry by heart in school, still don't; and I'm much better at understanding things than remembering them overall. My brain resembles much more a CPU than a Hard drive
Therefore I would welcome a DBM because it would make fights less based on memory, and more on actual intelligence. For instance on Titan, a sensible raid leader usually tells people what's coming next: "landslide"… "plumes"… "bombs"… etc. That person would often have notes next to the screen, until they learned it by heart. But that's not actual raid leading… that's just making sure people don't get screwed by the latency… (in most games, few raiders fail to escape an AoE when they see it, and anyway it's a decent challenge since they can actually succeed; here even if I have my eyes right on my feet I just eat the AoE no matter what, even if I'm out). Anyway I'm not turning this into a latency rant, and we'll have to wait for 2.1 to see if SE's changes fix the matter. What I'm saying is that a DBM-like add-on would clearly help many players who fall a bit short on memory but are nevertheless good, skilled players. But it's a whole, and those with less memory might pull off more DPS/HPS for instance, or might be more reactive…
Which takes us to DPS meters for instance. If people use it to compare players, then it's just stupid. Some classes will often be above others, and furthermore less DPS doesn't necessarily mean 'bad player', because they might have spent some GCD's supporting others (such as throwing a heal as BLM/SMN to save a tank, or make up for a healer busy saving/raising someone else, or something like that). And anyway you can't judge the validity of a raider's play based solely off his final DPS/HPS. I'll always prefer a strong, solid, stable, reliable player, even if she/he isn't top DPS of his class, someone who's a good team player is just about all I ask (honest to own her/his mistakes, trying to keep in sync with other members, etc.), than a fast-burner who dies too often and is incapable of performing tricks out of his hat in specific situations (be a kiter, play with mechanics and so on and so forth). However, there's a threshold, a minimum that's required for a team to pull through. If I see a player with half the others' DPS, then no matter how good that player is at everything else, she/he should do something to pull off more damage—and from there we talk, see her/his rotation, compare with others of the same class, etc.
Like for DBM, if I see a person having DPS issues, I'll strongly encourage her/him to use a DPS meter, at least for some time, so that person can see where/when she/he's falling behind others (especially of the same class), and thus identify their shortcomings; and then talk with others of the same class to learn how to do it better. If everyone tries their best in a group, and sincerely tries to improve oneself, it's just better for the team overall, and it makes the experience that much smoother for everyone. Frustration is a strong issue in raiding, it can lead many players away, simply because there's fatigue when you do it OK and others make the team fail too often. And when you're the one who fails, it just makes you sad and it's discouraging. I should know, I've been there. So while not pressuring those who fail, trying to help them more than anything else, you also have to cater to those who do well and make sure they don't get too frustrated. A team is a whole, and all these things matter in the long run (pun intended)
So it's a whole, it takes several kinds of information to assess a player skill, see weaknesses and strengths, know who's better at what, and who needs to improve, as well as who does it well and could teach others… (knowing all this helps a lot when assigning roles during a raid, as a raid lead you should know who's capable of pulling off a huge damage burst, who's good at throwing out constant damage, who's a good kiter, who's a good multi-tasker able to both DPS and throw support heals/buffs here and there, who's good at interrupting casts, who's good a tanking a massive boss using defensive CDs, who's good at tanking and keeping aggro on a lot of targets, etc. etc.). It's a whole, but you need tools to know that whole, to have a clear picture of your players. It takes time too, Rome wasn't built in a day, and all teams are different. We just have to accept that some players will always be better than others at something, but rarely everything… so you have a DBM for those with a bad memory or too little experience, you have a DPS meter to see the hard numbers, you have websites to help people gear and customise their gear (when it's a feature of the game, not the case here), as a committed lead you also dig through logs to see how the team performs in real situations (globally and individually), and so on and so forth.
It all becomes quite intuitive once you're a seasoned raider/lead, all of this is just the 101, the obvious. You just have to be smart about it, knowing how to use these tools, and how they can help players (who needs what). Conversely how they can alienate players and should NOT be used. You know, a little tact, psychology, fairness, understanding with players, that goes a long way. And it's pretty much the same for all MMO's, some are just more complicated than others (this one is rather simple so far, there's very little if any customisation thus all members of a given class are just about the same (you can expect comparable results), and mechanics so far are quite basic—didn't try Twintania, stopped playing before, so I can't judge that one.
TL;DR: I'll take any tool that can help the team win, I just won't use them stupidly to judge people based on 1 single piece of data, nor will I force people to use them if they perform alright without. Did I say it was a whole?![]()