When I want to make a cross-sectional view of certain assemblies, I have the preview of the cross-section, but when I validate I get a message "Making a section in this place will produce invalid bodies. Please select a different section position". No matter how much I postpone the plan, he refuses.
My assemblies have almost all WWTP parts from Creo.
Indeed, it is an alternative. I did it directly in the original assembly, without a copy. There is normally not much risk.
It also allows me to visualize the parts that are causing problems, because SW warns that he will not remove material from certain parts. Once the "cut" is finished, the problematic pieces appear whole.
I do practice the technique of shifting. But in the case indicated, it is not enough. The problem comes from parts with errors. Piece that go into wobbly surface. And indeed it's almost always due to "zero thickness"
The palliative is, as indicated above, a removal of material in the assembly, throughout. And then he cuts almost everything, except the parts that are problematic for the cut. I can then spot them.