Phil, I know the Indian Garden (that started in the 70's) does not use any tomato in the base. I don't have the specific recipe and amounts as yet but it differs from most of the base recipes I have seen here. As much as I could glean from the IG Chef during the bhaji demo it's made up of half a potato, green pepper, half a lemon (pith & rind), garlic, ginger and of course onion.
I asked specifically why he doesn't use tomato and he replied that he prefers to add this at the final dish stage to give him more control over his dishes, both for flavour and colour.
Interestingly enough, the tomato paste he uses (White Tower) is processed thus: Fry garlic in oil, add tomato paste, water and mix.
The dishes generally are not as wet as you find with most modern BIR's. I'm too young to remember the 70's BIR but the IG does some cracking nosh.