How can you avoid gridlocks that may occur within Selenium Grid if a test fixture requires the use of two WebDrivers

Question

In a case where I require 2 drivers running at the same time, I fear that I can accidentally cause a gridlock within my grid.

Currently, I am running 3 nodes with a concurrency of 1, but I fear that if I scale this, I am going to run into deadlocking due to asynchronicity.

What is a good practice to avoid this from happening?