NO

1 decompositions
 #0 -----------
   1: g(x) -> h(k(x))
   2: g(x) -> x
   3: h(k(x)) -> f(x)
   4: f(x) -> x
   5: k(c()) -> c()
   6: f(c()) -> g(c())

unjoinable peak
    h(c())
*<- h(k(c())) ->*
    c()