I have one example. This happend here just a few minutes back.
So here I am staring @ some texture that is being rendered onto the screen. The problem though is that there are these thin lines (black) being drawn on the extreme edges of the screen. I tried a little here and there and then finally though that the UVs are being wrapped/tiled. The texture is half transparent and half opaque black.
Then walks in Jack Porter. Looks @ it, stares a little and then says something to me and he goes off to try his theory. Theory I said eh… it was the solution. Apparently he came across this problem once earlier. He changes the texture draw type to clamped and lo behold it works.
Guess what… experience matters. A lot more than we can imagine. What I can do in 1 hr he does in 1 minute.