So with that simple comment you are not invasive, or arrogant, you share an experience. If the person doesn't get it, then that is their problem, but you would be surprised how these little seeds grow.....
Again, I am sure you're right BUT I still live under the impression that my nose doesn't necessarily belong in other peoples conversations. SO I made the decision to keep mum on the subject. While I am the type of will freely admit that I don't know it all and will take advice that seems sound, there are a lot of folks out there who don't share that opinion. Just my .02.