Fascinating. Until now, I never even heard of this test. Ironically, I don't use it consciously either. By that, I mean that if the characters talk to me, they define the parameters of gender. I really feel these worlds are already established, and the characters simply allow us the privilege of seeing into them. (Which many famous authors have mentioned or alluded to.) The concept sounds silly, OFC, but if you're one of them who enjoys this privilege, you understand what I mean. For those who write differently, the concept is... difficult to relate to, I imagine.
Now regarding the ironic bit, I say ironic because the novel I am currently seeking to put on Amazon Prime has a nearly 50/50 ratio of male/female characters, with the males popping out in the lead by only one, out of a cast of seven. The bad guys, on the other hand, are at a 3:1 ratio. XD However, I can't remember if passes the Bechdel test, but if it does, it's by sheer coincidence, I assure you, LOL
The point I'm making however, is that I do not believe an author sits down with the sole intent, much less even a passing thought, of creating a work which will, indeed, pass the Bechdel test. Whether it does or does not, I believe this to be a product of coincidence, rather than design. In fact, depending on the numbers of the cast you employ in your novel, it would seem to me more a matter of numerical probabilities whether or not the Bechdel test is passed or failed.