I haven't read the 10 past pages in the thread, so forgive me for any answers I may have missed.

It might depend on the duty, but I don't relate to OP's experience. I'm running both low lvl dungeons, trials and all the way up to lvl 70 stuff, not counting raids and ex trials. I play DRG myself, so in most cases I am the party's first choice of dps LB. I tend to save it until the final boss, usually finishing off or close to with LB. I never hear anyone complain about that. However, sometimes someone else will pop it during an earlier boss, or even trash encounters, ie. for BLM's aoe. Also, the tank will occationally lead the party with suggestions on what to do when, and these tanks tend to tell when they'd like the dps LB to be used (boss usually, but also BLM sometimes on earlier encounters, and sometimes to save it for healer's LB if necessary).
There has also been occations where I've been too late to trigger my LB, and the other DPS has done it to finish off the boss.

So no, I don't think it's not a thing.