Actually Gorbag, I've read that making coconut oil your main fat during the switch to ketosis can lower the transition time. As I understand it, the MCTs in coconut oil more efficiently convert to ketones so as long as the MAJORITY of your fat comes from high MCT sources, you are theoretically able to produce more ketones quicker. It's not NECESSARY to do this when transitioning, but it can help.
But then again, simply fasting (without the added fat from your bulletproof beverages) should also keep the ketogenic state just fine after your "nightly fast" so if you really don't feel a need to eat anything on a particular morning there's no need to force the bulletproof beverage thing. I'd keep it to times where I want to maintain ketosis but need an influx of calories to keep me going.