Maximizing the system is filing IFR for me. YMMV. But outside of
departures from the NY and DC Class B areas, filing is the way to optimize
your use of the system. Don't always have to open it, don't have to stay on
it. But with GPS and good ATC skills, I usually can optimize my flight
paths and altitudes better in the system than out of it.

My experience is somewhat limited and geo specific however.

"Peter R." wrote in message
...
) wrote:

If you don't have a pretty good idea of where you are likely to
encounter
IMC en route, you haven't done a very good job of flight planning.

I disagree. Are you claiming that good flight planning will always
provide
an accurate picture of future weather, especially for a trip that covers a
large number of hours and miles?

IMO, experienced weather forecasters sometimes get it wrong. When they
do,
then there are going to be times when I, as the pilot who is planning the
flight with their products, will get it wrong.

Sure, one can simply cover all bases and always file IFR, but knowing how
to maximize the system seems to me to be the theme of this thread.

--
Peter