it's my main request too.
I don't know if it is related to zbuffer, as many others said, what I know is that whenever there is any barely ambiguous situation, the engine generate weird clippings.
The mother of all the ambiguous situations is obviously when there are intercepting polys, but it generate similar clippings in many other situations that should be safe, expecially when there are convex shapes, like engine inlets or when there are small details over bigger faces.
With inlets, the clipping is worse when the internal and the external faces are close to each other: knowing this it is possible to reduce the effect, but not to completely avoid it, and often it also mean to reduce the quality of the model and spend ages adjusting the mesh. If needed, I can provide a clear example of how scaling up the mesh (and therefore increasing the distances of internal and external faces of inlets) reduce the clipping problems