I know I cough when I'm feeling emotional.  The mucus flows; the cough
reflex is triggered.  There's no need to be unduly vicious in one's
condemnation of coughing.  Some people may cough deliberately, but most
must cough, ironically, because the music is moving them.  Consider
how many people cough *involuntarily* when embarrassed.  The habit of
*deliberately* coughing to express embarrassment has undoubtedly arisen
as a piece of body language inspired by seeing *involuntary* coughing due
to embarrassment.

Excitement, melancholy, joy, all these things induce coughing, and are
in fact aggravated by the need to remain silent.  So the symphony concert
is simply a chorus cough waiting to happen!  It can't be helped, short of
forcing everyone to take cough suppressants.  But those are central nervous
system depressants, and likely to have a significantly deleterious effect
on enyone's enjoyment of the program.

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