It did indeed seem that the significant majority of
time was spent 'viewing presentations/tutorials',
while the WG chairs frequently employed RED/discard
on the folks that occupied the queues at the
microphones in order to more promptly begin the
next tutorial and finish within the alloted time.
for many groups, the number of active participants is so small
that there's really no need for a microphone ... except that
due to the large number of passive observers they have to meet in
a room which is so large and so noisy that amplification becomes
necessary. and the medium access time for a microphone queue
is sufficiently large that having a microphone drastically
reduces available bandwidth at a meeting.
Keith