In this essential groove I'm channeling one of my favorite players, Robin Trower. Here we're going to use our thumb over the top of the neck to sound the root on our low string, giving us a really thick sound. This is a common technique used quite a bit by Jimi Hendrix, Robin Trower, and frankly just about every other guitar player I can think of! It can be a bit uncomfortable at first, as it's all about getting the technique right. Your hands may be different from mine and it may take some experimentation to get your thumb comfortably over the top of the neck.
Remember the thumb is only sounding the low string and comes over just enough to mute the fifth string. We're not trying to fret any notes on the fifth string. You'll see this technique a number of times in this course, as we did in my previous blues grooves course, Essentials: Blues Rock Grooves Vol 1. I cannot imagine playing guitar without using this technique—it's well worth your time and effort to get it together.