I think what puts a lot of people off is the making of the Base,
Les
Its for this reason why i think all newbies should be put onto CA's simple base
http://www.curry-recipes.co.uk/curry/index.php?topic=7645.0
For me, it tasted like any other good base and being only 2 onions is a quick no hassle introduction into BIR cooking. None of this "you what!?, i need a sack of onions, an armfull of garlic and ginger, giant pots. nahhh, i dont think i'll bother."
Frank. 
I'll second that, Frank, and that's exactly what I do when any friends or family show an interest (though I've been using small versions of my favourite bases, as I hadn't seen CA's until you posted that link. Will give that one a try for def though, as I'm a huge fan of simplicity.)
It's all about getting them hooked and witnessing how simple it all really is, and means that you can say, "Of course, if you want to make up a big quantity you have the option", rather than the other way round and putting them off before they've started.
As for who will continue to carry the curry flame after I've shuffled, well, I'm lucky that everyone in my family is curry crazy. (This is entirely down to my parents, who were early converts to the cause when the first restaurants started opening up in London in the late 50s / early 60s.)
My brother is an excellent exponent of the BIR art, and my two daughters wield a pretty mean chef's spoon, too (insert proud dad smiley)...