All I am saying here is a free form adventure centered on characters (both pcs and npcs) isnt a railroad just becau the gm takes a "how would this npc logically react to this" approach.
You are so focused on your specifics that you are completely missing the general point, which is what I, and Perkins made. Not all NPCs need to be Fat Tonys, or King Oswalds, or any other of a million "my precious little NPC".
The railroad occurs because the DM keeps putting the goals of "my precious NPC" above the goals of the PCs. The asshat NPCs occur because the DM keeps treating the PCs like they are second class citizens, and every NPC is an antagonist by default.
My illustration is a general comment about the extremes. The railroad occurs at the extreme. When the goals of the NPC have no intersection with those of the PCs, and the DM keeps putting that NPC in a position to influence a scene that is where the railroad occurs. That might be an extreme, but it's still a railroad.
You can play the Dragonlance modules as pretty freeform adventures if you really want. There's a lot of good mineable material there. You don't have to follow the script, if you will. But the PCs have to be invested in the world, the NPCs, and what is going on for this to work. How is that going to work if every NPC from Tika the barmaid, to Goldmoon the "priest", to Otik the proprietor of the Inn of the Last Home always behave like asshats towards the PCs? That is what Perkins is talking about.
Of course you need antagonists. But for it to work you have to look at the NPCs and determine up to where their sphere of influence extends. The sphere of influence of Fewmeister Toede is obviously different, and much more limited than that of Dragon Highlord Kitiara, or Verminaard. If the PCs avoid getting captured in Solace, by Toede, but then just keep running into Toede is that not a railroad. In the Dragonlance modules the important NPCs had a mysterious death clause. That is the epitome of a railroad. My little precious NPC didn't survive first contact with the PCs, guess I'm going to have to bring him back from the death. That is absurd, but that is what non-intersecting goals of PCs and NPCs create.
I can take the material from the Dragonlance modules and run an entirely non-linear, non-railroaded campaign based solely on the goals of the PCs. The issue is that I need their goals to have an investment in the world, and what is happening to it. If every NPC that they ever encounter is an asshat I've dissolved any chance of their goals ever being investment in what happens to the world. Why should they? Everyone in the world that I have presented to them deserves the PCs contempt anyway. That is Perkins point and in a very round about way is what I meant by railroad.
