There are so many different aspects of this software. Im not to familiar with the buses and subgroups but they are useful when you can use them properly. Ive been playing with random mixes from the internet and im getting used to the layout of protools. i know how important it is to make sure your levels are in the right spot before you bounce and making sure you bounce to the appropriate format. Theres so much that goes into a mix from start to finish. Even laying out markers to identify certain points in the songs just to make it more functional.