Wow, thanks for that update. Super-confusing that the CBIC guide would contradict the RBI. When the RBI published its updated rules in 2014 there was some buzz in travel forums about the relaxed currency regulations, which is where I had heard about it.

I'm certainly not a lawyer and no-one should rely on me for advice on such stuff but I wonder if there's even a possibility the guidebook has simply not been updated correctly? The CBIC's website that lists the specific customs rules for currency only points back to the FEMA notifications, which are what the RBI notice references.

Anyway, this is probably getting off-topic for this thread. Probably best to go with the more restrictive rules in any case. Although I'll say that in years of traveling to India I've never heard of anyone being checked or questioned about INR being carried out (and even some cases where the officers seems to have seen INR and not cared about it).