I asked if that is what she was thinking of, but she was adamant that she remembers a single recipe .bb file that could do this. Is there such a thing? I suspect one could hack something up, but is such an approach considered standard? Or even doable?
Doable? Yes...Smart to do? IMHO, absolutely not.
With the recipe class methods that accomplish each stage of the build you can customize them any way you want, but at the expense of maintaining clear intent and keeping it maintainable.
Your initial approach of using common includes and a heirarchical inheritance for separate recipes makes more sense.
i suspected as much, i just wanted to confirm there was no super-clever way to do this.
