I'm just now coming to the point in the story where speed runs are happening, and I know that the community is pretty divided on the topic. I'm personally against it, because it just flat-out ruins the experience for a story focused player or really anyone new. Here's my suggestion to forever destroy the concept:
Boss is dead, chest pops, hidden calculation happens (% of mobs killed in dungeon x tomestones = what you get), if 75% of mobs present weren't killed then no reward
Easy examples: Castrum Meridianum normally drops 100 philosophy, but your group skipped all the trash and only killed what they had to = no reward. 80% of mobs killed = 80 tomes, 100% killed = 100 tomes.
No, it's boring and silly.
Forgive my harsh tone, but maybe you haven't been grinding Amdapor Keep for the last month like most of us. People against speed runs, generally, fall into this category. I am required to do 8 runs per week to cap ToMs or I fall behind. That's 8 X 45 minutes, which is what a good party can manage without speed runs. The dungeons are pathetically boring when your party is overgeared, healing and tanking can be slept during and even DD can just hit 1 ability and clear it with this time and no problems.
That's not fun content.
The proper solution would be:
A) Provide additional avenues for ToM grinding (which we'll see in 2.1)
B) Add Tomes to the enemy drop pools, in addition to the current rewards. Make it a small chance, I don't care.
But when you make trash mobs drop 1 *****ing gil and all they do is break your gear (exp gain = gear dmg) you do very little to incentivise the population to kill them. I would rather speed run it in 18 minutes (still currently doable) and use the rest of my time leveling something or crafting or helping people with Titan.