Haven't been on the forums in a bit, but to respond to this:
On enrage timers and being blind:
We have the Stone, Sky and Sea. The dummy's HP is tailor to every job and is meant to show that if you keep up whatever you are doing, you can complete this fight on this class. It takes into account mechanics that need to be performed, otherwise you'd end up never being able to pass the SSS dummy. What it doesn't tell you is if YOU can still sustain DPS while doing mechanics. Great example: I see melee come off Lakshmi when they get the cross mechanic, even if they are the only melee. During the whole time they have this mechanic, they are not DPSing. They can completely sit on the boss and sustain their DPS; all that mechanic requires is for you to not stack them with other mechanics that are happening. Things like this show people are more than capable of clearing the fight (if they did the dummy), but execute poor understanding of the fight to actually do it correctly and incur needless loss. A result page at the end of a fight won't change this. Showing personal DPS after a fight won't change this. Doing research, like watching streamers that are good players, or videos put up by YouTubers that are good players, can change this.
How much death affects your DPS:
Weakness and Brink of Death debuffs tell you that your main stats are reduced by 25% or 50% over a time of 100 seconds (and another 100 seconds for Brink of Death if knocked out while you have Weakness). Considering your main stat is only ever second to weapon damage, that's a HUGE reduction. You don't need to actually see the reduction to understand that's absolutely terrible.
PvP result page:
So... you want a leaderboard. That's the only thing it serves in PvP. It shows how much was healed, knock-outs, assists, damage to players and damage to environment. PvP and PvE are cats to dogs. How you DPS in PvP is not the same as PvE nor will you heal in PvP the same as in PvE.
On healer LB:
It's a progression tool. The only fight that ever "needed" it was A4S. Most fights, it won't save the group because if you're already at the point that you need it, more than likely, you're just going to die again because of lack of understanding to the fight or mechanic. Dun Scaith was a great example of this; watching groups wipe, saved by healer LB and wipe again. Only to have the group that actually understood the fight never use healer LB and carry everyone else to the clear.
I cannot imagine hitting enrage on a primal due to no deaths. I've been in a group here or there where DPS wasn't the best, but still cleared. No deaths. Were people just AFKing or auto-attacking? Or were they doing silly things like coming off a boss unnecessarily, like in Lakshmi? Which is pretty common from what I've seen. Still, never seen enrage being hit from sheer lack of DPS on 0 deaths in any of the years I've played since ARR launched sans in raids/savage. On the contrary- I've seen more wipes due to too much DPS than lack of DPS. Either you're that unlucky or I'm that lucky.
Still, a result page at the end won't change anything you're complaining about.
Nor would a parser.
Nor would anything sans simple research. However, the problems you're speaking of already exist from a lack of research.
And very few of those mechanics have long lengths of downtime, especially compared to Alexander, which had huge lengths of downtime (okay, some fights did and others did not). Longest bouts of DPS loss I can think of are "animal farm" (which the DPS should be failing the last mechanic only to maximize DPS), taking the physical/magical buffs since they put you into the Out of Action status, the proximity adds, or breaking vines. Everything else I can think of, you're always hitting something. So, yeah, it's mechanic heavy, but mechanic heavy need not mean DPS loss heavy. Even with Spellblade Holy in library phase, you have enough time to hit the boss between that mechanic and Squelch to not suffer any real loss.
Then look at something like A5S. A fight where you will be dropping all buffs/rotations to do the fight's mechanics. Multiple times.