OK, here goes, first post.
I used Pat Chapman's Curry Bible recipe for well over 10 years. Despite many attempts, I found that his curry masala gravy invariably tasted harsh and somewhat bitter. Few people liked many of the recipes I cooked from the book. They all lacked a 'rounded' taste, and none resembled a BIR dish.
There are, however, two recipes that IMHO are tasty, aromatic and well worth cooking. The first is his Keema Balti made with lamb mince and cooked in the oven. It reminds me of something you would get from Mother India in Glasgow (yes, I live in Scotland). It ends up as a dry-ish curry, sort of like a risotto in texture. It does have that integrity that one looks for in terms of satisfying taste.
The second is his Methi Gosht (sp?) which again used lamb. This is more savoury than spicy, but again has that lovely rounded taste.
I write this because someone asked, I think, if there were any recommended PC recipes. I would recommend these, although not as BIR exemplars, just tasty curries.
For BIR I am now using Julian's base at C2G, and await his forthcoming e-book. Just saying.