As long as you smoke, the cake will build, no matter what you do, no matter what you smoke, no matter how you smoke (unless you use sandpaper, as the captain said above). This is what I believe.
After each smoke, I always clean the bowl with a paper towel, but a hard cake always builds up.
In this pipe i only smoked 8-10 bowl. Also this pipe had no coating from the factory. the briar was clear.
In this pipe i smoked around 30 bowl.
I've had this pipe for 2-2.5 years, and I've smoked it much longer. I have also sanded it 1-2 times with sandpaper.