HugM,
I don't think a note on the safety card would do much good. How many pax ever read them anyway?
Also, to go a little off-topic for a moment, how many pax really listen to the safety briefing given by the F/As.
I always laugh at the guys who act bored and make a point of reading newspapers, looking out the windows, etc., while the F/A is giving the speech! Same mentality as the secret GPS, mobile, etc., users! They are important and cannot be bothered!