It should come as no surprise that timing and groove are the most important qualities a drummer should have. You can play the most virtuoso beat ever played on the most expensive drumkit ever built, but if what you're playing does not groove it's basically worthless in 'real life'. Heck, I even named this whole endeavour The Quest for Groove. If that doesn't tell you what's the most important to me then nothing does.
All lessons and courses I make are always taking timing and groove into account. So in a way it doesn't really matter which course you're taking, as long as you do the exercises I tell you to do, you will be working on your groove. By the way, the notion that with timing you either got it or you don't is simply not true. It can be practiced and improved, just like almost anything else.
On this page you'll find the content that has timing and groove even more on the forefront than normal. Enjoy!