An appendectomy can be done quickly and easily nowdays, but did you know how awful it used to be? That was only 60 years ago, when they had you in a bed for a week with stitches, many many stitches up your abdomen. And, surgery on the eyes for cataracts had you immobile for days with braces on your head. Today it is a walk in procedure.
So... E6 vs Kodachrome. - same difference!
I have some ideas on this though regarding easier means to Kodachrome type results using B&W film. I would be interested in your source for Color Developers and your source for Couplers.