Other arm?Used too, stopped using it though. I like to be able to have the whistle in my mouth blowing for a foul, as I'm signalling which direction (Can't do that with a lanyard attached to wrist).
Other arm?
I managed without for a few seasons but then dropped my whistle when the ball hit my hand and had to switch to my reserveI keep mine in my palm. I've never had a problem (not saying I won't ever have one).