I calls 'em as I sees 'em 
This True-Fi mess we should have seen coming because even to this day old Soviet diktats survive that the customer is far down the food chain so shouldn’t be warned in advance that a ‘life license’ simply means the license would be valid only as long as the licensing company kept making the product covered by the license. In North America this would never fly, with court injunctions regarding consumer rights would be raining down on Sonarworks. But Sonarworks is not in North America, it’s in Latvia and, like all former Soviet republics know too well, Western companies rarely bother to pursue such cases because it’s extremely costly and, more often than not, leads to nowhere. I can only speak for the US and Canada whose legal systems are somewhat familiar to me (I have dual citizenship having been born in Canada to American parents). That by no means make me an attorney but I possess reasonably good common sense, or so I like to fancy.
I believe that what would likely have happened here is that Sonarworks would be held liable for their lacking of a clear definition of what they meant by ‘lifetime license’ and, since they are by no means under bankruptcy (yet), be ordered to offer the replacement product Reference 4 Headphone Edition (similar to True-Fi but with way more sound shaping options) to True-Fi licensees at no charge. That would have been fair, because what they’re doing now certainly isn’t. They don,t seem to realize that prospective corporate clients -which means potentially good business- don’t have much appreciation for unethical tactics that shoo away customers. Latvians or not, it doesn’t make a speck of difference because revenue is generated by sales not by goverment policies like back in the Soviet days. If they keep this on they won’t last long. One needs to deliver.
I have continued to occasionally swap out my Elegia and Elear under somewhat controlled conditions to see if I can really hear a clear different between the two using a mostly flat eq. I can usually make the swap in about 5-6 seconds. I should also add that I am around 55 and have my hearing checked annually as part of my job and it is mostly normal with a little high end drop off. But otherwise pretty normal.
Congrats for being youger than me, I was already born when JFK was shot though I was only 2 months old.
The way my doc talks about my hearing sounds pretty much the same as you: some loss in the treble area but not much to write home about. Youèd think that the heavy machinery operator that I was would be more affected but I was one of those suckers who always wore ear protection so my age-related loss is within population average. 680-hp 8-wheel monster tractor makes a lot of noise… mainly from the CD’s I was blasting in the cab while drving it lol
Despite keeping notes of observations and time stamps I keep coming around to the fact that I really can’t hear a distinctive and consistent difference between the two and the biggest difference comes down to the lightness and openness of the open back Elears versus heavier and almost sound canceling feeling of the closed back Elegia.
I can’t either and it’s the same for several people I know. Methinks it’s because the crossover roll-off happens at a lower frequency on the Elear, but it’s just a theory based on the fact that the unusually potent low-end of this can never bleeds into the (timid) mids, contrary to the less massive but more invasive bass on the Elegia.
As far as eq’ing the signal…all bets are off, of course. I can eq. the signal at the driver level and find that all my headphones benefit from some eq’ing on a song or genre specific basis. And that’s just the way it should be (again, in my humble opinion).
Well if it’s of some value to you I have always EQ’d cans based on the headphone response to a flat noise rather than tune it for some specific piece or genre. It’s much more consistent and can be achieved with a DSP bandpass filter, which are simpler to design than parameteric EQ’s. This will only work good for planars and very few dynamics though. Right now I’m using parametric EQ and still am amazed at the SQ the Elear can extract from it. That 'phone was probably more complex to design than I previously thought, considering it’s been used as the matrix for all high-end Focals except for the Utopia. Now bring on that Stellia so I can load those CC’s to the max again Can’t wait
The variation in preferences between different sound engineers, mixers, technology, target listening environments, and what I personally find appealing is just too great for a one size fits all solution. Fortunately, 9 times out of 10 everything sounds great right out of ‘the box’ and only when I’m somewhat bored or really engaged do I tinker with eq’ing the signal to really dial it in. Others mileage may vary, or course.
The EQ’ing should be used to build a solid sonic basis, itès when you try to fiddle with mids that you are the most likely to f… up the whole affair. The trick is to make use of that priceless feature, the shelving EQ which is best for achieving even response within the ‘presence’ region without affecting phase rotation noticeably. You also got to pay attention to two settings that many neglect: gain and preamp values. You have to use gain for every frequency you are adjusting, not a global, so-so quality single gain control like those found on basic graphic EQ’s