Hmmm . . . my question is: can atrue data separation model be achieved in FileMaker? By this I mean the "data" part is input pure and simple. The recording of keystrokes and nothing more. No calulations, nothing. Simply a Primary Key and input. If it's even possible the amount of work would be huge. I think the separation model in the context of FileMaker is over-rated.
Actually, splitting a data base file to produce two files, one interface and one data is quite simple to do. It does not require "re-pointing" any fields in the interface file.