any harm in allowing only ctrl-Q to restart output?

[Henry Spencer]

Strictly speaking, ctrl-Q should be the only thing that restarts output.
The fundamental problem is that flow-control protocols really ought to
be implemented so that they are invisible to higher levels, notably to
the user, and XON/XOFF isn't.  So we have a fundamental confusion about
whether the terminal is invoking flow control to slow down (not stop)
the flow of data, or whether the user is invoking the same machinery to
stop output for some potentially-unbounded period.  The decision about
restart characters depends on which of these cases is occurring.  If the
user is stopping output, restarting it on any input character is a much
more "idiot-proof" approach.  Ctrl-Q is not exactly an obvious combination
for a user who is wondering why in $^%$^% his terminal won't respond.  It's
not too bad if he stopped output deliberately, but if he hit ctrl-S quite
by accident...!  On the other hand, if the terminal knows about the flow-
control protocol and is using it deliberately, then violations of it are
fraught with potential problems, as you're discovering.

There is no entirely satisfactory solution.  Given that the violation of
the protocol is fouling up the terminals, your best solution is probably
to make the change and live with the occasional "my terminal is hung"
phone calls that will result.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry