Part of the problem I think is that "incremental" is a relative term. What's huge to one person is small to another. But I'd say in the case of the 3.7's, the typical reaction seems to be more in keeping with yours -- the improvement is more than incremental. But I've heard someone else say as Doug did that he thought it was in incremental change.
One thing that's true, the .7's have major changes -- quasi-ribbon rather than wires, single-pole crossovers, improved power response, better midbass. So technically, there's a much bigger difference between a 3.7 and a 3.6 than a 3.6 and a 3.5. Magnepan has made it clear that they weren't going for an incremental improvement on the 20.7 -- Wendell Diller was quoted as saying they wouldn't release it until they could make a significant improvement.
But even if the difference is bigger than it is for the typical new model, there's still going to be an element of subjectivity in the description. It's entirely possible that two people will hear the same exact sonic changes, and one person will say "nice but incremental," while another will say it's the best new thing since sliced bread.
Ultimately, I think the only thing we can do is listen ourselves, as you did.
One thing that's true, the .7's have major changes -- quasi-ribbon rather than wires, single-pole crossovers, improved power response, better midbass. So technically, there's a much bigger difference between a 3.7 and a 3.6 than a 3.6 and a 3.5. Magnepan has made it clear that they weren't going for an incremental improvement on the 20.7 -- Wendell Diller was quoted as saying they wouldn't release it until they could make a significant improvement.
But even if the difference is bigger than it is for the typical new model, there's still going to be an element of subjectivity in the description. It's entirely possible that two people will hear the same exact sonic changes, and one person will say "nice but incremental," while another will say it's the best new thing since sliced bread.
Ultimately, I think the only thing we can do is listen ourselves, as you did.