The fastest way to break this rod with zero fishing skill is to fish in the small ponds at G-6, H-6, or I-6 all the way in the back basement of Gusgen Mines with Meatballs (which you can purchase from the Fisherman's Guild at C-8 in Port Windurst for ~52 gil each).
from an old fishing guild. hope this helps some people trying to break to synth there.