Does Time alignment and Phase coherency make for a better loudspeaker?

...my statement refers to aiming for a perfectly flat measured speaker response as a sonic end point

But the thread is about the time domain performance of a speaker.

One cannot change that too much with DSP. The impulse response can be cleaned up somewhat. But in the edges of the crossover bands it is not really possible to do much in a passive system compared to an active one.

Once the non-time/phase aligned system and the time/phase align systems are in place, then either/both can have the frequency response dialed into what ever is asked for.

And the question then that the OP sort of asked is, "will they sound different?"

Y’all get the crappy lossy cabinet output shows up in the impulse response, and more importantly the waterfall...right ? All easy to hear.

Mijo in 1983 I was using an FFT program on a Commadore PET in the design of loudspeakers.... I feel like Lew... hackles and all

But the thread is about the time domain performance of a speaker.

One cannot change that too much with DSP. 

With my DSP controlled active speakers I can set them to linear phase or low latency the former is delayed 30ms to align the drivers the later turns off linear phase for a 3ms delay. I can't tell a difference but my room isn't an anechoic chamber. 

Ever heard any of John Fuselier’s loudspeakers from "back in the 80’s"? Time and phase aligned, with excellent coherency and pulse response. Soundstaging and imaging were exceptional. Spectral balance varied between different iterations/models, but all had an uncanny ability to sound real. If you are familiar with them, then you should know exactly what I am talking about.

Time alignment is about when the sound reaches your ears from the drivers in your speakers. Getting it right adds realism to the sound. Wilson Speakers are built to be listened to time aligned. The smaller models are not adjustable in that regard and require a setup within some relatively tight parameters to sound best. Not to far from the listening posistion or too high/low. The middle and upper models have adjustable modules for each driver alowing more flexbility for the seating posistion and room size. Is it night and day? Yes if you are used to listening to your system with $50K and up speakers, well set up and driven by really good amplification and sources, so at least six figure system. Otherwise, not so much. This is a final touch for well designed systems.