I've using the KD base for some time with what I think are good results, although to be fair I have not tried others so I'm not really in a position to comment!
I use use his base with a recipe based loosely on several that I've read about; plus what I'ce seen done in the Kitchen of the 'Gatwick Tandoori' (now the 'Zari') in Ifield (Crawley, West Sussex).
For years I loved their Madras/Vindaloo, and when I finally got to see it made I was surprised by some of the ingredients!
The Chef had a 'stock-pot' of base on the cooker, and it looked very like KDs in colour and consistancy, This is how he did it: First he 'swirled' a oil arround a small frying pan and put it on the hob to heat, next he added a small amount of the base (I'm guesing, it was a long time ago but 3/4 tbs-ish), next he added some 'curry powder' (looked pretty much like Bruce Edward's 'mark 2', the stuff that contains commercial basaar) plus some sugar (!!) and some chillie powder. After that cooked for a few moments he added the remainder of the base necessary, cooked it for 5mins or som added some chopped corriander leaf and, interestingly, a few 'shakes' of Lee & Perins Worchester Sauce!
I was very interested to see that the chef only had 2 spice mixes for ALL of his dishes: the curry podwer I mentioned above, and also Chat Masalla; so it just goes to show that in inteesting variety of dishes can't just depend on spicing alone!
As for his method, I assume the initial small addition of base was to provide an enviromment for the hot oil to extract the flavour from the spice mix, without the risk of burning the spices. The water in the base sauce will prevent the tempreture climbing above 100 C (unless all the water is boiled off!) The relatively small amount of base allows the relative excess of oil to to do its job. I've tried adding spices later in the process but in almost all cases the result is not as good! In my humble experience the only spices that benefit from being added later are: cummin and the mix known as 'Garam Masalla' both of which burn easily and/or lose flavour if over cooked.