Interesting reading this thread

I have watched my curry being made at some T/A & Restaurants and as yet have never seen the wok on fire yet the curry's fantastic so I don't personally believe you
have to catch your curry alight to achieve a delicious curry .
Also I make experimental changes to the way I make my regular Saturday night Madras , Pilau Rice ,and Onion Bhaji's and have found the following.
Base. (Onions,Garlic,Red Pepper,Carrot,various Spices)
* If you don't already, add enough Salt to give your base some ' taste ' like you would if you were making a Beef stew.
* Not tried yet but instead of covering your Onions with water why not use stock cubes to enhance the flavour of your base ?
Pilau Rice.
*Fry your Rice in Butter and Oil before you add your water for boiling, deelicious
Onion Bhaji's.
* Try using plain flower instead of Gram flower,very nice not so ' heavy ' batter.
Madras.
*Tried Onion paste a few weeks ago,Yuk ! spoilt the flavour of my Curry.
*Tried adding fresh chopped Chillies at the Garlic/Ginger frying stage to see what difference they would make to the taste rather than just my usual Chili/Mirch powder.
Just increases the ' burning' sensation and continues to burn for some time ! whereas with Chili powder you get the initial heat but doesn't last as long as with Chillies.
*I use about 9 Tbs of oil for a 3 portion Madras ,I put a small amount of oil in the Wok to fry the Garlic/Ginger etc then when I add the spices which 'mop up' all the oil I add the remainder of the oil.
*My wife commented on how the house smelt like an Indian Takeaway when she turns on the deep fat fryer !this is due to me cooking the Bhaji's in the fryer which have various spices in them but this gave me the idea of using some of this oil for my Madras ( Spiced oil and all that ) and the result was no difference to fresh oil

*My wife reckoned my Madras was a little 'thick' and needed thinning to give more sauce so I added some water which made plenty of sauce but killed some of the flavour which she agreed

it seems to me to be critical how much water you add to affect the flavour.
These are only my personal findings and most of my curry's have been delicious, at the end of the day it's all down to personal taste but I will continue with my Quest.