How to make Executable Matlab files in Windows run faster concurrently ?

When I run two executables concurrently they take double amount of time to run. The MCR is single threaded so running the compiled exe in another shell (command prompt call with &) doesn't help. This is running on a very fast 6 core i7 machine with 64 GB of ram. Is this a problem with JVM contention ?

How do I make two executable programs in Matlab run faster in Windows Server ?

Is this a limitation when you multiple compiled executables?

I'm hoping someone at Mathworks can answer this very simple question.