The point at which the stick is held should also be the balance point of the stick, the balance point meaning how far along the stick you should place your grip so that the maximum response is gained from the stick.
This point can be found by placing the stick over the first finger and dropping the stick onto a practice pad or snare drum (see photo). The greater the number of natural bounces the stick makes, the closer you are to finding the balance point. The balance point occurs roughly 1/3; of the way up the stick (from the butt end).
It is important to relax your hold on the stick, as too much pressure will "choke" the stick. The more relaxed the grip, the more easily the stick can pivot within the fulcrum. This leads to a better sound, greater endurance and greater speed.
If the height of each individual stroke and the height between the two sticks is the same, the resulting sound will be even and constant.
If you follow these three rules when practicing, your stick control should develop quickly. The best way to obtain speed is to always remain relaxed, and to practice precisely.