Hi curryhell, I'm pretty much settled now that subtle differences in base gravies are neither here nor there when the strong flavoured ingredients I'll add later will dominate. I read Julians book yesterday, where I'll have to hand it to him regarding the effort he has put into it, I won't make his base gravies as i'm pretty sure they won't tell me anything new.
The most important piece of information I took from his book is related to what's been termed singeing,
which is to remove the acidity from the tomato paste & in my view the spice mix which also taste acidic when undercooked. I'm not sure about releasing oils in the spice mix(who can tell when that's achieved?)

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But I do know that if I don't remove the acidity at the frying stage, it'll be there until the end. It's probably causing lots bir@home cooks to turn out curries described as "not bir" The high heat commercial burners clearly do this far quicker than at home, & trying to replicate the cooking times shown on the kitchen videos may be causing even more problems. Cooking out the tomato paste may take even longer if using the tubed supermarket stuff, as that tastes even more acidic than the Salkim I use.
I've ruined many a great madras.........by adding too much lemon juice at the end ;D
Garam masala instead of MP, as in Ashoka produces some great curries as c2g has also stated
Would like to get c2g view on Vegetable ghee
**edit - cooking /singeing / releasing oils from the spice mix would take a hell of a long time at home,if ever on Julian's recipe's
(1 TBSP) 
I've been using 1.5 tsp max

Regards
ELW