After reading all this I'm still confused as to the actual use. Isn't a triptych or diptych is a series of 3 or 2 photos, usually related in some way? I could understand (I think) doing all this if you were aiming to print the whole neg (either contact or enlarged) as is, but when different emulsions (& colour and B&W) are mentioned, what are the benifits? (I can see the benefit of the two panoramic images placed on one piece of film). Since your reducing the amount of negative your using, why not use a smaller camera (interchangable back MF)? unless the need for movements is mandatory (which probably would be to get the image onto the bit of the film you're aiming for anyway)

Pless enlighten me (I won't be able to sleep otherwise!!!)