Great link. I love it that RAS Syndrome is an example of itself.

I think a very relevant part of the article is “A limited amount of redundancy can improve the effectiveness of communication”

The prevalence of “PIN number” suggests it’s a useful redundancy.

Someone tell The Los Angeles Angels.

RAS 'syndrome' is just an example of redundancy in language, which is often actually useful for communication. There's no reason to insist on avoiding it.

I always use my PIN number at the ATM machine.