Why, in heaven's name?

Two-Face goes back to the 1940s, which I think pre-dates Sholay. A much more likely influence is the George Raft character in the 1932 Scarface, who also tosses a coin, but doesn't use it in the same way as Two-Face. The Raft character was well enough known that the coin flipping (by another character) was used in Some Like It Hot.

I don’t want this to sound patronising, but I found the ridiculousness of the plots, the melodrama, the bigger and life acting, essentially their naivety was a mark of their cultural purity, their independence from Hollywood.

I don't mean to sound naive but isn't this part of the point of Bollywood? To be bigger, more melodramatic et, al, than Hollywood films. Aren't they having some fun at Hollywood's expense?

I'm not claiming to be an expert and am willing to accept that in recent years Indian cinema may have moved to another level. It can be a bit of a struggle to keep up.

Admittedly, Indian culture is highly visible (and popular) in Britain, and must be having at least a subliminal influence on the mainstream. It may be harder for me than for an outsider to see this influence, but I'd say that for a number of reasons, film has been the perphaps the most resistant medium to this influence. I'd say Indiania has tended to be an option rather than forging some sort of fusion and that art by non-Asians that has self-conciously borrowed from Indian culture has often struck a false note.

no.

...reason is only a subset of rhetoric

I guess I'll just wait for an explanation from someone else.

Hmm.

You speak as if all your nazi purity propaganda is fact.Tjis is furthest from the truth.I could explain but why should I need to convince you about it? it's pretty self evident that this is happenning to me.