YES # Parallel rule labeling (Zankl et al. 2015). Consider the left-linear TRS R: h(f(f(c())),b()) -> f(h(h(h(c(),h(f(h(c(),f(b()))),a())),b()),c())) c() -> c() f(f(h(h(f(a()),a()),c()))) -> f(h(f(c()),b())) h(f(h(f(b()),h(h(f(h(c(),f(c()))),b()),a()))),h(a(),c())) -> c() All parallel critical peaks (except C's) are decreasing wrt rule labeling: phi(h(f(f(c())),b()) -> f(h(h(h(c(),h(f(h(c(),f(b()))),a())),b()),c()))) = 1 phi(c() -> c()) = 1 phi(f(f(h(h(f(a()),a()),c()))) -> f(h(f(c()),b()))) = 1 phi(h(f(h(f(b()),h(h(f(h(c(),f(c()))),b()),a()))),h(a(),c())) -> c()) = 1 psi(h(f(f(c())),b()) -> f(h(h(h(c(),h(f(h(c(),f(b()))),a())),b()),c()))) = 1 psi(c() -> c()) = 1 psi(f(f(h(h(f(a()),a()),c()))) -> f(h(f(c()),b()))) = 1 psi(h(f(h(f(b()),h(h(f(h(c(),f(c()))),b()),a()))),h(a(),c())) -> c()) = 1