Unite, indeed!
However TheBrain poses some issues on that point. Pardon this longish post on the problem.
I am very invested in TheBrain as part of my workflow – nowhere near your million thoughts, but somewhere in the 28000+ range, with 74000+ links. I feed MyBrain from items collected via Bookends (which are auto indexed into a DevonThink db as well), and my goal (an unfulfilled wish at this point) is to use the power of Tinderbox to “curate” (in Michael Becker’s terms) material drawn from various parts of MyBrain to facilitate completion of various (but related) writing projects. The problem has been how to get the relevant thoughts into my TBX file. Not easy to figure out for an amateur like me, and TheBrain does not make it easy.
Over the last week or so (thanks to help from @archurhh and others in another thread on this forum), I was able to extract a group of thoughts (a few hundred for a test run) into an md file and through the explode function was able to populate my TBX outline. However there was a glitch related to either delimiters (or perhaps Brain links) that made the importing a limited success.
So the impression seems to be that TheBrain makes efforts to “unite” extremely difficult and therefore limited its integration into workflows such as mine.
Would be interested in your view on that (as well as any solutions…)