Another thought that occurred to me. I read in some posts that the practice of curry cooking in the 80s, included the use of a whole-chicken in the gravy pot.
I tried it, scaled down, so I added a portion of chicken to a smaller quantity of base sauce.
The result went against all my understanding of western cuisine, at least, in that meat/poultry adds enormously to the flavour of most sauces. Well, it added to the flavour here and seemed to knock out and dominate the curry flavours. In other words, the chicken made the base sauce and final curry worse. I mean to try again and again to see how I can make good use of fresh chicken stock in BIR type curries, without them going downhill. Perhaps it's as simple as just adding less.
I know it should be possible. Loads of curries start with raw chicken and taste good. For example. Madhur Jaffries recipes. The Dhansak spice mix I thought was so good, used fresh chicken as well - so it must be possible.