Hi MBC
Not knocking your personal Quest, as its quite humorous
Gave me the vision of you smelling the curtains and carpet of a BIR in whatever bygone decade. ;D ;D
One waiter to another -
Oh! thats the guy who smells the curtains - matadoss ;D
Its probably true of most expats, who long for a British Indian Curry
and romance about the golden age of the 70s / 80s curries.
(CA and a few others spring to mind) nostalgic nonsense and a fruitless pursuit of something unattainable.
Nothing retro about your dish as its not based in reality
Onion Powder, Garlic Powder, All Purpose Seasoning, all a bit of a nonsense.
NOT USED in a BIR Madras or anything else and never were, even in the 70s
I can remember fresh Coriander used as far back as the 70s
A pinch of Coriander and or Methi Leaf in a Madras still is and was dependant on the Chef.
That Old Bhaji/Chip oil notion.(Chestnut)Never did see any BIR kitchen reusing Bhaji/Chip oil to start off a curry in the 70s,
mainly because your 70s curries were made with vegetable ghee.
You might not be used to writing recipes,
but you seem to be confusing yourself with Methi powder in your recipe and Kasoori Methi in your method
Fenugreek (methi) Powder is a secondary spice in BIR and rarely has a use.
Anyhoo, thanks for posting.

cheers Chewy