Maybe this may help clear it up a bit.
Not only is there no such thing as a 100% neutral speaker, and while it's true that every speaker has a degree of faults, the faults that different speakers exhibit are............well...........different.
If we take Nin74 example regarding high frequency performance only, than yes, the speaker that has less high frequency distortion "should" be considered more neutral..........but..........what if that speaker that has less high frequency distortion has more mid frequency distortion, or more distortion off-axis than on? Than that speaker may well NOT be considered more neutral. And then add to that the factor of room acoustics where one room may make one speaker sound more neutral and another room may make another speaker sound more neutral.
There are just wayyyyy tooooo many variables. Then when you add to those variables, the variable that all of us has different tolerances as to what we can accept and not accept regarding speaker performances, not only with what we psychologically prefer, but also our varying physical abilities in how we perceive sound, is it no wonder that peoples opinions will differ as to what speaker is more neutral than the other?
So yes, all speakers have faults, AND they exhibit these faults in many different ways, AND all the faults vary from one degree to another, AND these same faults that speakers have is also present in MANY different ways both in our physical ability to hear as well as our personal preferences as to what we like or don't like.
So with that in mind, there is just no way that one can make any kind of general statement regarding speaker neutrality and how ANY of us would preceive that neutrality. (and to those that may quote the Olive papers regarding the double blind test at Harmon, that was only measuring neutrality in ONE facet of speaker performance and that was frequency response).
I know that this has been all said before, but I just thought I'd reword it a bit to see if it made any more sense to those that disagree.