I am not familiar with the pseudo-chicken you mention Sverige. I've never seen it in our grocery aisles.
Having never been any where near an actual British Indian Restaurant, as in located in Britain, I'm not able to compare my output with the standard you mention George.  It doesn't sound great though, so mine may well be pretty good after all.

I will try the diagonal cuts next time around with lower degree of cooking to see if there is any discernable improvement.  I'm quite happy to eat the dark meat and actually prefer it in some cooking, but the main dish I've been tryng to emulate is for people who prefer white.  Life is full of little challenges.

It's funny how things have changed. When I was a University student 40 years ago living in shared digs, chicken generally, and breast fillet in particular, was only rarely affordable on our low income budget. Today it is the cheapest of all meats.  Breast was always more expensive than thigh but recently this is often reversed. 

Warming everything in the oven.
Spread half eaten.

I know that chicken white or breast meat is drier than red meat like thigh or drumsticks.  I also think there is a big difference in meat today with massively grown meat birds.   I recently did Misty Ricardo's pre-cooked chicken following the instructions to the letter including the sauce covering and additional oil.  I thought it was fine but the only criticism from anybody after our banquet last night was that most of my (very fussy chicken eating) family, thought the breast meat was a little bit dry.  Mind you there was nothing left.

Maybe I cut the pieces too big. I do like large pieces. Maybe I over-cooked but it is a moisture cooking process. I'm not sure.  Perhaps I should arrest the initial process when the meat is only 75% done and finish it in the actual dish assembly.

I did see a video on Chicken 65 by Chef Harpal Singh, where he is quite emphatic that chicken breast must be cut on the diagonal to the meat fibres in order to obtain tenderness.

Any thoughts or advice would be gladly welcomed.

I've gone back to my notes from making the lowest common denominator base gravy. As previously stated, I used half listed average quantity in the OP for all ingredients with the complete exclusion of any Chili.  I also omitted any coconut block or milk but I did use a 50/50 mix of coconut oil and ghee instead of vegetable oil to the 75 ml (50%) level.

Looking back over my notes, as it turns out I actually did just use 50 % of all the spices as well, including both Mixed and Curry Powders, again with the exclusion of Chili Powder.  This produced a very usable base gravy.  It has worked really well for my intended purpose actually.

My pressure cooker is a multifunction unit with saute mode so I was able to utilise it for the whole process.

I was wondering what others do with the amazingly intense stock left over from a batch of pre-cooked lamb. I can skim the oil off for spiced oil but it seems such a waste to tip the remaining liquid down the sink.