Equal terminal slices with unequal residuals

Now retain only the coarse terminal label $q_2\in \{-2,0,2\}$. Let ${\mathcal{F}}_{\mathrm{coarse}}$ aggregate the actual middle path maps. Define a second complete instrument ${\mathcal{G}}_{\mathrm{coarse}}$ with the same two outer branches, but middle branch

The middle effect is still $8I/25$, so the two instruments have the same coarse record law on every input.