Jim Root
This is the best pancake recipe on the internet but after making it for the last 4 years I've made a couple adjustments to make it perfect. 
1.  Increase baking powder to 4 tsp
2. Increase butter to 4  TBS and add it after you've mixed everything else. This will reduce the clumping. 
3. Add a 1/2 tsp Vanilla after mixing butter (should be the last ingredient).