I think the dual TRS is actually a pretty cool idea if you want to get balanced audio out of it. A pair of TRS to XLR connectors would be all you would need and you could route that to a stereo system or whatever. But for driving headphones? The 4-pin A&K type connector gives you the same pinout. I suppose it appeals to the same folks who have their headphones terminated for dual 3-pin XLRs 

And I'm certainly not going to drop cash on balanced cables to help it along in that regard.  That's not its reason for being, in my opinion.

I'm not sure I or Neil Young agree with that. It's designed with balanced output in mind, and don't you want to get 112.5% out of your music files? 

I agree, Neil probably wouldn't publicly agree with that.  He's a professional showman fronting a startup looking for investors. I take his sales pitch with a grain of salt. Take aside a guy from Ayre, however, and what could he say with a straight face other than "Yah, we built a great little $400 portable.  If you want to hear something really good, check out our home components."  The balanced output capability of the Pono is cool, but we both know it just makes it a turbo-charged Civic.  If someone wants to spend a quarter or more of the Pono's price for balanced cables, all the power to them.  Just don't expect it to run like a Porsche.

Sorry, but I more often hear an improvement in balanced output sonics compared to a headphone than not. It actually makes sense. TRS jacks are just a convenience design and have a number of intrinsic electrical drawbacks (noise, shorting, etc.). Whether you believe they are audible is up to your experience, testing regimen and chosen belief set. Electrically speaking, it is more advantageous than TRS, no doubt about it.

Meh for analogies. I know some turbocharged civics that would and have run circles around some stock Porsches. It's all relative.

I'd also say the balanced output from the Pono is a notable improvement not that far removed from what you get upgrading from an iPhone to the Pono SE. You already paid $400 to get to that point, another $100 give or take ain't that far off if you've already gone down the rabbit hole. Ultimately it will depend on your chosen transducer and your listening priorities. I just wouldn't be so quick to dismiss the idea when taken in the grand scheme of things.

I don't doubt that the balanced output sounds better.  I just don't see many folks--me included--bothering with balanced mode and the added expense of the cables.

That's totally fair. I see merits to both alternatives.