1hook,

I don't think that by using thread wraps you would increase the chances of the tip section of the line sinking. However, that said, I seem to have problems with the tip section, like the first foot or two, sinking. I clean and treat my line before every say of fishing but about halfway through the day the tip portion seems to like to be under water more than on top. So, I give it a treatment again, this time using a product that is made for on the water use and that resolves the problem, usually for the rest of the day. While water may look clean, it isn't and there is a lot of buildup of matter on the lines that cause them to sink, hence the cleaning.

Larry ---sagefisher---