I wrote:
This is one of the more brain-dead things the FAA does. There may be good
reasons why, from an internal FAA point of view, there are two sets of
routes. From a user perspective, however, it's absurd that they're not
folded into a single table.

Marco Leon mmleon(at)yahoo.com wrote:
Not really.

Yes, really. The AFD contains two sections with preferred routes.
One is called something like "Low-level preferred routes", the other
is called "TEC routes". They both contain routes from origin to
destination, with certain altitude, speed, and time restrictions.
From my point of view as a user, it's just extra work to have to flip
back and forth between two different sections to find what I'm looking
for.

The two sets of "preferred" routes (like Peter pointed out) are
due to altitude restrictions dictated by the traffic flow from the
KJFK/KLGA/KEWR trio.

No, they're due to the fact that some routes go through ARTCC
airspace, and some don't. This may be important to the FAA, but from
my point of view as a user, I couldn't care less whether I ever get
handed off to somebody with "center" in their name.

This is further driven by the runways in use. With the possible
departure/arrival combinations from the three airports, it would be
very hard to guess the preferred route of the moment.

There's no doubt that the routes in use change to adapt to weather,
traffic patterns, facility outages, etc, but that's not what I'm
talking about. All I'm saying is that if they're going to publish a
bunch of routes, they should just put them all in a single place so
they're easier to find. Splitting the information into two distinct
AFD sections is just plain stupid.