Garp, can I ask why you use the Asafoetida / Hing? If in fact you did include it.
My understanding of this ingredient is that it is used either to reproduce onion/garlic flavours in dishes eaten by certain groups of people who can't eat root vegetables for cultural / religious reasons, or as an addition to vegetarian dishes, particularly pulses and legumes, to control methane production in the gut. OOOPs

, bloody dog.
As the recipe already contains garlic and onion and base sauce, which I assume has onions, is there any reason for it's inclusion? Not having a go at you, just curious that's all.
By the way it looks great and I especially like the consistency of Unclefrank's effort. That is exactly how I like my curries to be made. I've got a heap of boned out lamb in the freezer so I'll go get some out and have this for tonight's dinner I think.