the PS behaves much like GradCAD print. Which is used for industrial 3D printers which I use at work. I say GrabCAD is the "worlds slowest slicer" but it is analyzing every layer and how each line is connection to the layer above and below. It extends the top and bottom layers to connect to infill lines much like PS. The only setting new in 5.X which kind of helps mitigate this issue is in Infill under Top layers is a top layer Extra expansion have it it at least expand far enough that the flopping edges are not visible from the out side. This setting was much welcomed and solved a ton of strength issues of low infill part for me. the issues is still there. Since these edges will flop down with low infill then the low infill expects something to be there when it is not. Some of theses fancy infills fail horribly if something is a little off.
I will say the S3D seems to be the fastest slicer I have ever used. It does not analyze each line but analyzes areas within each slice then applies a pattern to each area. This would probably take a complete rewrite of S3D to make this work better.
