What really hasn't been touched on was that the "old" AFTMA stuff was for earlier generation fly rods. We've been hacking around this for years about the newer rod technology and why companies constantly bring out new rods. I think we've arrived at the point where we realize that in order to stay in business the companies have to do it to stay competitive. The change in the line recommendations represent the change in the rods over twenty years ago. Almost every rod is so much faster, stiffer; you fill in the adjective. The charts/line weights merely represent the needed poundage to turn over flies on the new rods. That's why guys are constantly overlining them with their older lines. Think about it...
umm too bad most new rods are not better than they were 20 years ago.. just stiffer and lighter.. Things were perfect before now they are worse and as a result of some manufacturers marketing campaigns the whole industry is screwed up.. leading to the mass confusion of everyone who hasn't been around a while.
buy a double taper and learn how to cast beyond the length of the head.