Jerry,
I found that alignment of the tweeter/midrange pod to be crucial. It is a little more involving than setting up the Europas. When the time alignment wasn't right and the tweeter arrival time too soon, there was a sharpness to the sound that could be unpleasant on some recordings. That was when I just set the up initially w/o doing the proper procedure, just plopped them down and eyeballed things. I wasn't enamored at first like I thought I should be. But I heard enough goodness to know there was more to be had.
I liken it to the first time I heard a pair of Maggie 1.6s in a store many years ago. The setup was awful and the room had terrible acoustics. But I heard enough to know that I wanted to buy them. And after getting them into my system in my room, they sounded very good.
Bottom line is that Roy's speakers require more time and effort than run of the mill products, but the end result is worth it. He can fill you in on more tips to get the best out of the Europas. And the answer to your initial question is yes, I think the time coherence thing is real and contributes greatly to the sound. But I also think driver choice, cabinet construction and a simple xover make things sound more real too.
Shakey