YES # Parallel rule labeling (Zankl et al. 2015). Consider the left-linear TRS R: +(0(),y) -> y +(x,0()) -> x +(s(x),y) -> s(+(x,y)) +(x,s(y)) -> s(+(x,y)) +(x,y) -> +(y,x) All parallel critical peaks (except C's) are decreasing wrt rule labeling: phi(+(0(),y) -> y) = 3 phi(+(x,0()) -> x) = 1 phi(+(s(x),y) -> s(+(x,y))) = 3 phi(+(x,s(y)) -> s(+(x,y))) = 5 phi(+(x,y) -> +(y,x)) = 2 psi(+(0(),y) -> y) = 6 psi(+(x,0()) -> x) = 6 psi(+(s(x),y) -> s(+(x,y))) = 5 psi(+(x,s(y)) -> s(+(x,y))) = 5 psi(+(x,y) -> +(y,x)) = 4