Norm, you've made my point about what works, or is relevant for some people, might not work for someone else. You say, "I guess, became more of a P3D thing since most other add-on folders in P3D are contained outside the root sim." Then you say "The recommended practice of simply placing files into the scenery-world-scenery folder or sim folders has changed a bit for P3D users whereas now placing any 3rd party scenery-world-scenery (ai traffic files, Effects, 3rd party add-on scenery, simobjects etc etc) in it's own folder external to the sim. These things apparently pertain to the way P3D users organize things than to the way FSX or FSX SE users do, or apparently can.
Dex,
I'm the one who is advocating, "if it aint broke...." It shouldn't be difficult to troubleshoot AI problems if something goes afoul because we have people who understand this stuff and can usually sort things out in a hurry. Just my opinion.
Steve
Steve