MS Access databases on slow network: Is it faster to separate back ends?

I have an Access database containing information about people (employee profiles and related information). The front end has a single console-like interface that modifies one type of data at a time (such as academic degrees from one form, contact information from another). It is currently linked to multiple back ends (one for each type of data, and one for the basic profile information). All files are located on a network share and many of the back ends are encrypted.

The reason I have done that is that I understand that MS Access has to pull the entire database file to the local computer in order to make any queries or updates, then put any changed data back on the network share. My theory is that if a person is changing a telephone number or address (contact information), they would only have to pull/modify/replace the contact information database, rather than pull a single large database containing contact information, projects, degrees, awards, etc. just to change one telephone number, thus reducing the potential for locked databases and network traffic when multiple users are accessing data.

Is this a sane conclusion? Do I misunderstand a great deal? Am I missing something else?

I realize there is the consideration of overhead with each file, but I don't know how great the impact is. If I were to consolidate the back ends, there is also the potential benefit of being able to let Access handle referential integrity for cascading deletes, etc., rather than coding for that...

I'd appreciate any thoughts or (reasonably valid) criticisms.