One potential solution to the parser 'problem'

[Sebazy]

Or they can enable a build-in parser selectively - i.e. It's only available in non-DF dungeons.

At this stage it's pretty safe to say that there is a reason that they haven't implemented this. Likely Yoshi doesn't want an easy way for the player base to 'demand' specific numbers and targets out of everyone regardless of how casual they may be.

So essentially, you want a parser, that only displays vague data?
While I'm not a fan, it totally fits SE's Modus Operandi.

However, the problem with this negative outlook on parsers is based purely on anecdotal evidence. In WoW, and other mmos, I've always used parsers as a method of comparing what I did wrong and right as far as damage (there are detailed breakdowns available in all) when comparing to other classes in the same encounter.

Oh I'm totally with you in this regard. My idea isn't aimed at you or I though.

The way I see it, this is aimed at the casual player who maybe only plays a few hours or simply doesn't play at the sort of level that more progression orientated people want. The sort of person who doesn't understand of keeping dots or self buffs up, let alone optimal rotations and such. They might well get called out for subpar DPS as they start to dip their toes into the end game and currently, they have no legitimate option for even attempting to figure out what they are doing wrong (e.g. figuring out dot damage is a horrible mess and time stamps are far too vague to get a handle on self buffs such as greased lightning). Putting something like this in would present these sort of players with some means of getting a handle on how far off the mark they actually are. The systems are already in place as demonstrated in PvP and it's simple enough to take those numbers and simplify the results down to a simple A-F style score.

The next step could be to reference the results against a weighted table to offer feedback for that person, failing combos? Dots failing off? Self buffs not being kept going? All super easy to prioritise and and turn around into some words of encouragement with their score. Keeping it fairly vague (aka no hard and fast numbers) is precisely as you say, it absolutely stops people from using it as ammo against others and allows the results to be tailored to different jobs, a monk might be expected to dish out 1200dps to get that A*, whereas a SCH is going to be about half of that. Again keeping it fairly vague neatly sidesteps the ever unpopular topic of tanks and dps accessories by keeping hard and fast numbers out of sight but giving feedback that gives them an idea of the difference they can actually expect to see in encounters.

As stated at the start, this is not a concept aimed at someone working on Alex savage, these people will without fail be working with full fat parser data be it directly or indirectly. This is squarely for the sort of person who is fairly new to MMOs and level cap content and actively wants to start upping their game. Dressing it all up as a saucer mini game is simply a far more enticing carrot than a random dummy sat somewhere <3