I was reviewing the manual trying to find any insights on lures or whatnot and at the back almost they have a tip to use the name HBMAX. What it does is change the depth meter's function for fishing and fighting.

Fishing it increases to display the efficacy of your fishing technique and it's attractiveness to the fish - instead of depth of the lure.

Fighting it increases to show the strain on your line while reeling. Sounds normal up to 10, and line breaks seems like maybe the first "tick" ending at/above 12.5.

Ultimately it doesn't really change how the game functions or what fish show up or how easy/hard it is to catch them best I can tell. I'm not sure it'd be super beneficial once the game is learned, but it would be helpful for learning how to play at least - having a numerical queue on how you're handling the lure as well as one to help gauge when you'd lose the lure.

I personally don't see why it would be disallowed. I doesn't seem to give an unfair advantage over someone who's practiced and wouldn't need the visual guides anyway.

I'm planning to do some more runs with it to see if it affects ranking or whatnot too, but the manual never claims to do anything other than change the functionality of the depth meter.