All I know is that since the implementation of the screen/layer plane there seem to be many more problems.
DXF export, STL export, displaced objects and symbols while editing, erroneous viewport behaviour, text not printing properly, viewports not exporting all the information etc....
I have been using VW for many years and although there are times when there maybe user error, I am normally fairly adept at using the software but since 2010 my workflow has slowed down, even though I have taken the trouble to learn new approaches to accommodate the 'improvements'.