Bughaboo, I understand this completely, but what you're saying is applicable to every brake system in existence. My statement is that there is an inherent design flaw with the rear brake line routing which accelerates the entry of air into the hydraulic circuit.
Your regiment could possibly take all the air out of the line perfectly and for good. However, we don't know this for a fact because your need to have a working back brake (as do I) so you don't give it a chance to fail and preemptively remove any possible air. So in essence like me you don't have faith in the way Ducati made the back brake hydraulic circuit and compensate by bleeding the line every 2 months, which I believe you shouldn't have to do.
I've had plenty of bikes with brake fluid that went black but never once lost line pressure because air never got into the line in sufficient quantities (yes I was young and dumb). I've read of people paying for some super high priced brake fluid (Castrol SRF racing brake fluid at $95 for a bottle 1L bottle
) with a higher boiling point to try and mitigate the situation with these bikes. Yes it does work to a degree, but why should we have to go this route or do a by monthly gymnastics routine to make a rear brake work.. we shouldn't. That's all I was saying.