I don't know if you can answer this, but still, why Obsidian, a relatively little developer, with a not-so-relatively troubled history, continues to focus on two teams with two games at a time instead of doing the (natural imho) choice of simply focusing
JES: Publishers pay us to staff with a given number of employees. That number is typically a lot less than the full developer roster at Obsidian. Additionally, tying yourself to a single project means that you are effectively at the mercy of that single project. Milestone payments, publisher relationships, etc. all rise and fall with the fate of that game. Publishers also know this, and can leverage that vulnerability to the detriment of the developer.
By working on multiple games with different publishers, milestone payments are staggered, there is more flexibility in moving employees around, and the individual publishers have less leverage over the company's daily operations/fate.