Technically, I can see no reason why this wouldn't be possible, but sifting through the OpenOCD docs has left me scratching my head a bit--actually, a lot! Most of the documentation and examples surrounding OpenOCD/JTAG programming of flash memories seem (understandably) geared toward more modern targets, like CPUs with boundary scan and MCUs with integrated flash. I guess I'm hoping somebody can refer me to a lower-level example or tutorial where pin/bus mappings are generally defined (ideally without assuming that all of the pins on the memory bus reside on a single TAP) and then used for programming. I'm 99.9% sure that such a thing exists, but for my particular aim, I'm finding that the signal-to-noise ratio is a tad low.
(Also: Responses like, "What the heck? Why would you bother to do that?" are totally appreciated also.)