NO

1 decompositions
 #1 -----------
   1: F(x1) -> A()
   2: F(x1) -> G(F(x1))
   3: G(F(x1)) -> F(H(x1))
   4: G(F(x1)) -> B()

unjoinable peak
    A()
*<- F(x2) ->*
    G(A())