Ha Ha! Funny this is brought up because one of my prep persons whistles a LOT! I dont know why but it drives me crazy!!! Luckily I am not always in the kitchen during her prep time AND she is an excellent worker so I grin and bear it!
Agreed, I cant see how whistling would introduce any more spittle into the air than breathing, and certainly not as much as talking, which often restricts the flow, resulting in greater velocity, hertofore to be termed salivosity, especially when employing such sounds as Ssses, th-es, F's...etc.
As to listening to it, if it's a stress reliever.... well it does beat having a saute' pan thrown at me.
it is a habit,
most likely not even aware they are doing it, and if they stop as in asked to they will hum this like those that click their nails, or constantly check their phone,
if they dont do it they get anxious and uncomfortable,
i would put 20 on it if you asked them to stop your prep levels will drop.
the reason i know this is i have one of these at work she must bop her head while prepping how the FK she dosen't loose a digit i am unsure