Hellooo!
I've noticed something inconsistent with blend modes and layer clipping when setting up some shadows.
It looked like the Multiply blend mode was stronger when the layer was clipped (as in it's darker than if it's not clipped), so I did some testing and it seems like blend modes act weird if the layer texture has partial transparency and it's clipped.
Edit: In this example you can see that the clipped layer it's darker and the only different setting is the clipping.