Thanks Russ, I've already got exactly the same pan! You're right about not claiming 100% as it leaves nowhere to improve on.
I tried the singe technique for the first time on Friday and had a partial success. Unfortunately I let the garlic go brown and ended up with a strong burnt garlic flavour. I cooked the spices quite long and hard and they didn't look or taste burned. I managed to eat the curry (just) but the burnt garlic flavour was quite a spoiler. A pity as some other nice flavours I don't normally detect had developed. I would also agree that when properly cooked the chilli powder has a hotter effect.
Next time I won't cook the garlic for as long. Do others brown the garlic or stop short?
Cheers,
Paul