I was using it to gain off of. the closer u are at first helps the gains for me to go up faster, and as I moved out a few tiles every like 3-4 points my gains stayed better, seems like the gains are horibly slow if u just start out in deep deep water.
Only took a few hours to get to GM from 60. I started as close to shore as I could and just moved 2-3 tiles out more n more till 80ish then just set the boat out a couple screens from shore and let it sit n got the last like 20 in like 10 hours, I died once during the 10 hours and not sure how long I was out so not really sure how long it really took tho