Pedrillo,
One of your questions concerns the "why", and that I cannot answer without getting into speculation about the engineering that I am not qualified to discuss.
However, about a year ago I replaced most of my system with MBL 111E, MBL 8011AM mono amps, and MBL 5011 line stage preamp. All at once, I retired Vandersteen 5 speakers powered by Ayre V1 amp and Ayre K1 preamp. I felt it was important to pair the MBL speakers with MBL amplification, since the speakers are power hungry.
I mostly listen to classical orchestral music and some jazz, and I attend live concerts often. The sound of live music is my reference, and attaining realistic reproduction of a full orchestra is quite a bit more difficult than reproducing a small jazz ensemble. In my experience, this MBL based system has made me truly happy. Prior to this, I had spent much time and money attempting to reduce the level of my un-happiness. The improvement is not incremental, it is a qualitative leap. This system now has a sense of life and energy that I experienced only once before, when my speakers were Martin-Logan Quest, but those speakers had a serious lack of coherent bass. I have been told that Martin-Logan's latest models are much improved in bass response, and they certainly are less costly. However, if you like their sound, do not skimp on amplification as electrostatic speakers are power hungry as well. I recommend at least 100 wpc and be certain the amp can deal with the speaker's wide impedance swings.
However, the MBL combination has no significant faults that I have found in a year of listening, and I am likely to gain additional realism by improving the front end (turntable). For the first time ever, I can come home after a live concert, put on an LP, and not hate the comparison. Most highly recommended.