ducksterman,

I have searched and looked and cannot come up with the article I read, but, did find this information which is interesting. From reading, I think fluorocarbon is less visible under water as a single strand because light is passing through it, but, once several strands are twisted together, I feel that this will interfere with light passing through it and it will lose it's ability to become less visible underwater.

Here is one article I did find which was interesting:

Refractive Index
The refractive index of a material is a measure of how much the speed of light is reduced as it passes through the material. Water has a refractive index of 1.33, meaning that in water light travels about 75% of the speed it does in a vacuum. The average refractive index of nylon monofilaments is about 1.58, meaning that when passing through nylon light travels at about 63% of the speed it does in a vacuum. Fluorocarbon has a refractive index of 1.42, meaning that when passing through fluorocarbon light travels at about 70% of the speed it does in a vacuum. Since the refractive index of fluorocarbon is closer to that of water than is the refractive index of nylon, fluorocarbon is theoretically the less visible material when immersed in water. That’s the science, and we hope it does more for you than it does for us.
We’ve tried for years to come up with a practical test of the comparative visibility of fluorocarbon and nylon monofilaments in water, without any demonstrable success. We’ve immersed fluorocarbon and nylon tippet materials of similar diameters side by side in water—in water glasses, sinks, aquariums and saltwater shallows—in depths from a couple of inches to over a foot. We’ve even tried photographing them under water, but we’ll be damned if we can see a difference. Both materials appear equally visible against a wide range of backgrounds.
That being said, the only view that counts is the fish-eye view, and in many years of using both nylon and fluorocarbon leaders and tippets in every conceivable fishing situation it is our subjective impression that fluorocarbon produces more hook ups than nylon. That conclusion is based on nothing but observation (albeit, thousands of them) any is completely lacking in any empirical data. Nonetheless, fluorocarbon appears to be less visible to fish, and for that reason alone it’s worth using, at least under certain conditions—like on the flats—where any degree of added stealth is a clear benefit.