The Synchronous Communications option can improve performance up to the order of 10 times. You enable this simply by specifying the /sc parameter on the fs.exe command line.
This improves performance greatly but has no impact on the ability of the client (in this case an enterprise server) to interact with the Fileshare server.
However, it means Fileshare polls the keyboard very seldom, so it is impractical to administer Fileshare from the keyboard - for example, you cannot close a Fileshare server by entering Esc. Instead you must use the FSView utility, which is briefly described in the section FSView.