@2pac888:
who thinks that in order to cross the red line have to go to the underwater mermen/fisherman island and when you are ready to go to the next island the underwater cavern or tunnel takes to the other side of the red line so you cross underneath the land using the water cavern or what not instead of crrossing over the red line
any thought as to my theory or theory of your own might good.
Unfortunately I don't support this theory. If you had to go to Merman/Fishman island in order to "cross" the RL, then it would imply that every magnetic path connects to Merman/Fishman island (which to my knowledge it does not). We're told that the paths eventually join at Raftel.
However, I do support the underground water tunnels or maybe even something similar to Reverse Mountain where there is a current that let's you go back and forth "across" the RL for each magnetic field.
After the SHs first entered the GL via RM, I had a theory that the official exit from the GL was at the 2nd intersection of GL and RL. I speculated that at this 2nd intersection, there'd be the option of continuing through to the 2nd half of the GL, or exiting to any of the 4 blues. Depending on where you approach to the RL would determine which field you connect to as you exit. Of course, this could lead to the possibility of having to wait a few days at the RL, and I actually don't like this theory. Not very feasible IMO, so I think the tunnels are a better speculation.