At the same time, exes seem to experience a totally obverse reaction, in saying that, because Prem can be so dissonant in his inter-personal relations, he was always a fraud in his 'mastership' in the first place.

I don't know any ex-premie who bases their understanding that Rawat's a fraud on such a narrow footing.  There are many, many reasons for seeing him as a fraud, the dissonance in his inter-personal relations merely one, and not a major reason at that.  Much closer to the mark is the fact that he once claimed to be the Lord of the Universe but was, in fact, merely the son of another man who, coincidentally, claimed to be the Lord of the Universe.  Even if Rawat was entirely consistent across time and across audiences, vertically and horizontally, if you will, in maintaining this facade, it's obviously just that.  His hypocrisy and crass, unintelligible mean-spiritedness is just icing on the cake. 

This polarity of attitude seems to me to be the cause of the problem of understanding between premies and exes. That either Maharaji is/was a great Master, or he is really nothing.

It seems to me that the truth lies somewhere in the middle. That, sure, Maharaji was never the Great Lord projected upon him, and which he himself came to believe. But neither was he a nullity. No - he was a person of some higher consciousness (at the time, but lesser so now?) who could make this apparent to others through his physical presence, and by the tapping of various centres of consciousness within them.

Further nonsense.  You can't make a silk purse out of sow's ear. You can't make a divine being out of a simple human one.  Rawat was just a boy.  A plain, old, regular human boy. Get over it, already.