If BO really works in the way it's touted, then yeah, in theory, increasing free T should lead to increased E. In fact, I'd think traditional AAs would hinder the effects, because you want some T for any pro-aromatase substance to work with.
Transfemme seems like a really expensive site to get herbals and glandulars from, if not an outright scam, but in some of their "promotional literature" and "testimonials" (that all read like second-rate transformation fantasy erotica), they specifically claim that someone using their (BO-based) program will boost their feminization if they were to be given T, as the body aromatizes it all to E and little to none becomes DHT. They also make claims about permanent and ongoing changes beyond a certain point, even after stopping use. I do wonder sometimes if that site is the source of some of the (mis?)information about BO that gets passed along.
I'm no expert, of course. I wish we had as much good info on BO as we do on PM. Lotus and others have done an incredible amount of research, so that when I tried PM for about a year, I had a vast wealth of knowledge to draw from. When I experimented with BO for a few months last year, it felt like I was flying blind in comparison.