@nmichaud, Thanks for the project code. I was able to reproduce the problem in all Corona builds (include 1262 for Graphics 1.0). I can reproduce the problem in the Corona Simulator running the Samsung SIII skin using a simple program that generates a two pixel newline and moves it around the screen.
The line width change occurs because of Dynamic Scaling. Scaling a 320x480 app to the Samsung SIII skin scales the line width to fractional values, which the OpenGL rendering engine needs to handle. The reason it shows up as an issue in your code is because of the changes in Widgets Tableview that cleaned up some formatting issues. This shifted the location of the separating lines from the previous widget builds and now these lines fall on locations that cause the issue when Dynamic Scaling is applied.
If you run your code on build 2100 or 2179, you don’t see the problem UNTIL you scroll the table. When you do that, you see the same issue with the lines stroke width increasing and decreasing as it moves up and down the screen.
Trying to get everything “pixel perfect” when Dynamic Scaling is used, is a hard thing to do and not sure what we can do to make it right and handle all scaling situations.