This topic is as old as the existence of superlines themselves but I've yet to see any compelling, "objective" study that has offered any solid evidence regarding the visibility of braid to fish, and whether or not it's really an issue. All we have is anecdotes. So, I feel compelled to offer mine. About 15 years ago I sat next to my best friend in a two-man boat while we slowly structure fished a very rocky levee with identical red shad power worms. My buddy had his texas rigged on monofilament and I was trying out some new hi-vis yellow braid (forget the brand) with my own texas rig. Over a 45 minute period, my buddy boated 7 or 8 bass of varying sizes. I don't recall any lunkers, but there were some nice bass. Finally, I dug into my bag and pulled out a backup reel loaded with tan (or maybe olive) braid which I proceeded to camo further with a dark green marker. I caught a nice bass on the spot on the very first cast using the new rig. I proceeded to catch fish for the next 30 minutes or so until it starting getting dark, thoroughly out-fishing my buddy. What I concluded from this all of this is that on that particular day, at that particular spot, those particular bass could see my high-vis yellow line and it affected their willingness to bite. I cannot say with any certainty that this behavior occurs on other lakes or other situations because I have never experienced such an obvious difference in results using two different types of line. The water was not crystal clear, but was lightly stained--probably 2-4 foot visibility. I have continued to experimented with coloring my braid and/or using flouro leaders for many years since and have often caught bass without doing either--although I never tried hi-vis yellow again without some kind of alteration. The only thing I can say at this point is that it probably doesn't hurt anything to camo the end of your line with a marker---I prefer a dark olive, or a "red-mud" hue of some kind--and....if I was a tournament fisherman, in it for the money, I would be inclined to use the flouro leader in any slow-fishing situation in clear, well-lit water. I don't think it matters one way or the other if you're pitching jigs at stumps in muddy water--even high-vis yellow.