One property of the route needed in this case is that it not go through
Potomac approach.

No. One property of the route =wanted= in this case is that it not go
through Potomac approach. It appears from what the controller said that
he didn't much care one way or the other. Now, maybe this controller
tried everything he could and in frustration passed it on to the pilot.
But it seems equally likely that Potomac just didn't want to handle
him, and my response would be "try harder".

I know - not very constructive, but I'm not in the air right now, I'm on
Usenet.

Your suggested response of "unable" isn't helpful at all and
suggests an unwillingness to work with ATC.

Their approach suggests an unwillingness to work with the pilot.

As I said in an earlier message, there are TRACONs that simply do
not allow thruflights.

IFR? At any altitude?

Why isn't that good enough? Once the center controller is informed that
Potomac approach won't accept you he has to revise your clearance in some
manner so that you do not enter Potomac approach.

Because the pilot has no reasonable way of knowing where "Potomac
Approach" is, especially since it changes with the whim and the weather.

What is getting my dander up isn't the situation of an approach not
being able to handle an aircraft at the moment. I'm sure it happens
many times. Rather, the phrase "what are your intentions?" in this
context (right after "we're not going to do this") hints at an
unwillingness of ATC to work with the pilot(*). ATC is there =for= the
pilots, not the other way around.

I wonder how many airline pilots have heard "XYZ approach is refusing to
handle you".

(*) I will note that that same phrase is very empowering to the pilot in
other situations.

Jose
--
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