Another good reason to use the rear brake, is to reduce front dive. A fact, that the more physically minded might be interested in, is that nose dive is only partially caused by load transfer. Another reason, and about as important as far as the front brake is concerned, if I remember correctly, is that the braking force, being parallel to the ground, can be broken up in a component that is at right angles to the forks, thus bending them, and another that is parallel to them and points upwards. So the braking force from the front caliper, working with your rake actively compresses the forks.
Coupled with the fact that the rear brake tries to lower the rear (because the torque it applies to the wheel, countering its rotation, is reacted on the swingarm) this allows the chassis to lower more evenly, instead of nose-diving heavily. It's quite effective, especially on taller, heavier folks, such as myself.
Nevertheless, I agree with the idea of temporarily keeping your foot off the rear brake, to get used to braking with the front. Be sure to drive extra conservatively and defensively while you're doing so!