Very interesting thread this.
I believe you come to your own conclusions after experimenting for years taking in consideration all your curry experiences over that time,I have cooked a curry in two separate takeaways plus had a days tuition in a Indian restaurant kitchen that specialise in 'traditional' style curry's that are made using very finely chopped onions and tomatoes to create the curry sauce/gravy and very nice too 
In my opinion 'the taste' needs to be in the gravy from the start and spices etc added at final cooking are only added to differentiate one dish from another.
My local where I cooked a madras use the 'all in the base' method where their gravy is basically a finished curry with only the odd ingredients are added to produce the desired dish and their curry's are very good.
When I think about it 'that taste' is the curry sauce in my curry the meat or whatever tastes of whatever the product is plus a light spicing probably from a marinating process but the flavour I really like is in the sauce.
I have made countless base gravy's and the finished flavour in the recipe is 'a mild onion soup' type flavour
Then on making the curry's even after adding spice at the final curry stage ends up dissapointing once again   
The best results I've had from memory was from the admin base which uses quite a lot of garlic and the gravy has that 'finished curry flavour' .

I see tamarind is in the list of ingredients.

Made the JB base last weekend, did the 2 hour hard boil and despite adding some water and giving an occasional stir ended up with 1/2" of burnt sludge on the bottom of the pan  Had to bin the lot !

@emin-j how do they successfully differentiate their dishes sufficient to create a full menu of different offerings?

I've seen pouring cream from a carton going into the frying pan probably a korma or ctm mixed with the ' all in one ' gravy but I guess any curry on the menu which comes in a gravy would be the same base, to be fair me and the mrs have madras plus my daughter has a biryani and the curry is not bad at all.

Quote from: haldi on July 26, 2014, 01:26 PM

I made the base and I thought it was pretty much like many I have done before
That was BEFORE I added the tarka and reboiled
That really transformed it
This tastes genuine
It's got that extra flavour

I'm having great difficulty believing that this simple tarka is really the final 5%. But then again I haven't tried it yet. And why has no-one else ever seen BIRs do this - crafty devils!  ;D

The thought occurs to me that it may be possible, as I have a freezer full of base already, to just add the garlic tarka to some reheated base and then blend. Would it really be that different? Suppose there's one way to find out.

And jb, as others also have asked, to what degree is the garlic fried?

SS it is only a 5% we have been missing, fingers crossed this could be it  ;D