Separating data from structure referencing the file to itself, possible approach?

Goal:

I've got a FMP file with a quite complex solution, I want to keep the solution in a single file, but I want also to separate the data from structure. The result should enable, when needed, to refer the data to another data source while being able to have the solution in a single file.

Possible solution (this is the question)

1) I reference the file to itself, using External Data Sources

2) I change in the relationship graph the references to the tables using the new external data source (which practically it's the file itself, but not logically)

3) when needed I could change the references in the external data sources to display remote data or to simplify upgrades.

Example 1 - I may install the solution file on the iPhone/iPad referencing it to FMP server, or I may install the solution locally on the iPhone/iPad referencing the data to itself enabling the user to download a single file.

Example 2 - I could duplicate the file using one file for data storage (a) and the other file for the solution logic (b)referenced to the former (a). This should enable me to upgrade the solution changing the file (a) with a newer one.

I've made some experiments using the Starter Solution "Contact Management" and it works

Does it make sense?

What are possibles issues?

Does it works faster on a gsm network giving the fact that the application logic is installed locally while the data are on FMP server?

Gianco