Understanding the mechanics of the sweep is essential if you want to improve your position and get to the top position in a fight. With the main strategy of Jiu-jitsu being position before submissions we are always looking to fight from the top position where we have gravity on our side and depending on if we are using our Jiu-Jitsu for a competition or a self defense/mma situation where our opponent does not have the ability to punch us effectively. The top position in a self defense situation is always better.
However the more somebody trains Jiu-Jitsu the better there balance becomes and sweeping people can become very difficult so we must implement other tools in order to be effective. In last nights No-Gi BJJ class we used off balance to cause our opponent to react and set up the calf slicer. The calf slicer is a leg lock which focuses on putting compression on the knee forcing the BJJ player on top to tap.
As Martial artists we strive to be well rounded in all of our skills, training in the gi is just as important as training without the gi, learning leg locks is just as important as learning choke holds and arm locks. As a martial artist the more you specialize in one particular aspect of a fight the less likely you are to be successful. Depending upon what your goals are in Jiu-Jitsu will shape how you structure your training.