In my opinion, A good bir madras does not include any potatoe flavor. If you add potatoe to the base then how can you arrive at a true bir madras. Answer: you can't. At least this is what a bir chef taught me during some lessons. His curries are superb, yours i have not tried, so i am inclined to believe him more than you. When i stopped adding potatoe to my base everything else improved. sorry if this pisses anyone off, but thats what my taste buds reported back. Its also what a very good bir chef taught me. try it, you wont be disapointed. if you are, then go back to your old potatoe habits.