I made this again tonight, using Chewy's base. This recipe really does tick all the boxes for me. Thanks, Chewy. I used chicken tikka, and standard chilli powder as I don't have any Kashmiri Mirch.
I backed off on the chilli a bit because of this, but man, was it still hot! I think Chewy's technique in the video not only gives a rich, caramelised onion taste but also seems to make the chilli heat more of an instant hit in the mouth, just like I get from good TA curries.
I do use the reduction technique but I've had cold feet in the past when it comes to worrying about burning and ruining spices. As a result my hot curries have tended to be 'slow burning', with the heat building up as you eat them. But this was an instant hit on the lips and the tongue from the first mouthful, and I think it's the first time I've had that without using fresh chillies in the dish.
Anyhoo, here are some poor-quality pics, suffering from the Jekyll and Hyde colour contrast between the pan and the plate. I guess it would be better if I took them by daylight, but I like to eat late.

Everything lined up and ready to go, in order to diminish the panic when cooking commences:

Bubbling away in my beloved 20-year-old curry pan. Like a flat-bottomed wok, but made from ally and about 3mm thick. Holds the heat brilliantly and evenly. Was once non-stick, but most of that has come away as a result of using metal spoons (and probably ended up in my stomach). I'm sure my curries have improved since the pan's become more or less bare aluminium. I'll probably take some wet-and-dry to it to get rid of the rest of the Teflon.

Chewy's lunchtime madras becomes Ian's supper-time feast. Not as dark as it looks here. Chappati? Yes, I had a great time. ;D

(Edited long, rambling sentence in the middle of the post. It was late, and I was rather 'over refreshed' when I wrote it.

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