I seem to recall that if the pressure at ground level changes by a certain
amount in a period of say 1 or 3 hours, then a generalisation of the
expected wind strength can be made. Am I right in this or is it a case of a
nice idea but ...? I'd have thought that the rate of progress of the weather
system would have something to do with it too.

You've got all the right ideas, but possibly not their relative
importance. The strength of the wind is approximately proportional to the
pressure gradient so if a system with a large gradient is moving the barometer
will change quickly and there will be a strong wind due to this gradient. But
it's perfectly possible to have a strong wind with the barometer steady if the
system is stationary. Equally, it's possible for the pressure to fall rapidly
with very little wind. An example of this would be the area to the northeast
of a rapidly developing secondary low.

Tudor Hughes, Warlingham, Surrey.