Thanks for posting this - this is genuinely one of the most interesting links I've discovered through HN.

I look forward to reading more comments and hypotheses. Currently the biggest questions is that raised by ankitoberoi - what other means could be used to manipulate the currency to such a large extent?

Sure RBI may be selling $ primarily. But what are foreign governments and private organisations doing? It is likely that they are also playing a role in currency manipulation.