Unique user logins on remote execution servers

The website we’re testing requires user logins and does not allow for concurrent logins with the same user. We use data binding for a login function that is called using “test as step” for each test. Each member of the team has our own XML file in our \Data directory with the correct username/pw data to use so that we can all run tests at the same time and not interrupt each other's logins.

What I’d like to do is run a number of remote execution servers to increase the speed in which we can test a build. However, when scheduling tests the remote execution server will use the XML file that’s on the system of whoever schedules the test run, so if they try to run on multiple execution servers at once they will fail as they are all trying to login using the same user and are constantly kicking each other out of the system.

The solution to this seems to be to use a coded step to swap in a new XML file before each test as detailed here:
http://docs.telerik.com/teststudio/knowledge-base/data-driven-testing-kb/dynamic-data-binding

I wanted to check to see if this is still the recommended method to accomplish this task before implementing it across our systems.

Another thought I had was to bind the login test to a file outside the data directory (for example, c:\logins) but I don’t see a way to do that.