Will Branchcache offer any benefit if the files are modified constantly and will BranchCache work with access databases that are being modified?

One of my clients read that Branchcache will speed up file access to remote sites.  As this might be true, their plan is to cache a mdb database file so that the remote client can modify the database while the local clients are modifying the same database.  Their other idea is to cache some Excel files that are constantly being used.  I don't see where either scenario will work and if it could work I don't believe it will offer any speed increase, but conversely fill the WAN connection with replication traffic.  I'd love to hear any comments to help support or kill this idea.