Practicing on a wooden cutting board - the djembe practice pad

I started practicing on a wooden cutting board about 6 months ago. After all this time I can say it turned out to be quite a productive exercise - in fact I noticed an improvement in the quality of the sound that I make on the real skin. The things you need: a thick wooden cutting board, a belt to tie the board on your legs, and an allready developed technique of hitting tones and slaps. The aim is be to be able to produce distinct tones and slaps while not hurting yourself even a bit. Not changing the position of the hand while hitting tones and slaps is also important. In this way you get the feeling of how to modulate the sound with the tension in each of the four fingers, and also you become aware of why and when exactly you should change the position of the hand for tones and slaps on the real skin. The bad side is that the wood doesen't vibrate, so for example there is no change in the sound when you keep your hands more or less stiff.