I am not sure what you mean exactly.
By ‘beveling’ the cut-in edge loop it has supporting edge loops inside and outside of the cut. It does create some 3- and 5-sided poles at the corners, but that’s where the Shrinkwrap comes in and that is also a reason to have a higher subdivision level on the target mesh. Due to the fact that the original and target mesh are already at the same place the Shrinkwrap Modifier does a really good job (and the projection method is not so important I think).
As long as the original mesh has a clean topology and you create the cut from existing edges, there should not be any pinching.
I’ve used this method a lot and never had any pinching issues, but if you do, please let me have a look at it.
