I think that an Aged Rope Phrase is
An anagram of a work by Edgar Allan Poe ("Aged Rope" is an anagram of "Edgar Poe")
Examples
Enamel Tar = Tamerlane
Enable Lane = Annabel Lee
Nice Beer = Berenice
He Houses Four = House of Usher
Adequate Ford Mesh = (The) Masque of (the) Red Death
A Lethal Letter = Tell-Tale Heart
A Nutmeat Atoll = Mellonta Tauta
Arterial Bum Pure = (The) Premature Burial
Hare Vent = The Raven
Deplaned Thump Unit = (The) Pit and the Pendulum
It seems as though the Not Aged Rope Phrases are
Anagrams of Works by Rufus Wilmot Griswold, a contemporary rival of Poe
Examples
Therefore Flows Typo = Poetry of the Flowers
Five Fog Lot = Gift of Love
Fifteen Smog Tint = Gift of Sentiment
Offer Loft Wigs = Gift of Flowers
A Affectionately Griever Mops = Gift Leaves of American Poetry
Fishermen John Tool Top = The Prose of John Milton