This whole, many-pages-long argument begun, apparently, with Ruf bringing up the double diurnal and purposefully overhealing as a "good" method of healing. Dunno how it turned into a forked argument of overhealing and damage, but whatever. That's not relevant for my post.
What matters is that, no matter what you, Ruf or anyone else may say, Savage/Ultimate are the two most difficult pieces of content in this game. They are the most challenging. They have everything the "lower" content have and more.
Now, what does that mean?! That what works in Savage/Ultimate will work EVERYWHERE. Meaning what works in Savage is universally good. What works in non-savage though...is another story. It may get you through the dungeons and easier trials, sure. But come across a harder one (still story, just harder) or simply a new one at a cap (aka Shinryu at release) and you'll fail repeatedly. A savage-level player will not. A player that does things that clearly do not work in savage, yes. Furthermore, even if you will compare the efficiency in a low-grade content like a random dungeon without any gimmick mechanics, the savage player will do stuff better, and everything else equal, the run will be easier AND faster for all involved. That is why what HyoMinPark among others is trying to give all this advice and spending 20 pages trying to explain this. It is BETTER and the more players will play the game better, the more fun it will be for everyone involved. Can't say that the content of this thread is rocket science though. Not even a cola-rocket one. It's something that every healer out there can stand to gain from.
This is math. The game is pure math. As such there is no anectodal evidence when taken even from a single case, so long as the actual numbers are used. It may be not representative of the average or the like, but it is guaranteed to be there as an option, thus valid. Players with high level of skill can show that skill with very high consistency, so they can repeatedly bring very significant results, more or less depending on the rest of the party. But as HyoMinPark and Bourne_Endeavor proved, the difference is significant.
Also, what is significant and what is not is more than just about clearing. 20% is 20%. That means that you get a "free run" every four you do. 10% is a free run every ten you do. Insignificant figures are ~1%, where the amount of time you save is lower than the expected amount of runs you'll make of that content. Otherwise it is significant. And it doesn't matter whether it's savage or just casual dungeon. Doing more content in the same amount of time gives more opportunities to enjoy yourself. More variety. If the run goes slow, I stop being able to pay attention. I make basic mistakes due to losing focus. And then I'm irritated that I cannot liven up to even my own average runs. I just have neither the patience nor the attention span nowadays to participate in a standard pull for almost as long as it takes to kill a boss with a good party. Yes, this may be a bit extreme case...but it proves the significance of people actually trying to be good in ALL content.
I jumped from topic to topic...sorry bout that. Oh well.
On a separate note...I like that image in your signature HyoMinPark. It's late here...don't judge.