> "Linguistically, an amphiboly is an ambiguity which results from ambiguous grammar, as opposed to one that results from the ambiguity of words or phrases—that is, Equivocation."
"Fixing" it would probably involve rephrasing to reverse the order of "people" and "pattern" in the sentence or
just put all the emphasis on the pattern:
"... these patterns, when discovered, have a habit of disappearing"
Strict correctness regarding subject:verb agreement can, like other grammatical constructs, lead to non-idiomatic, awkward phrasing. Formal "rules" about prepositions are the first related example I can think of. ("... of which I can think" is awful, right?). My point was just to laugh at the ambiguity. (shrug)