NO

1 decompositions
 #1 -----------
   1: +(0(),0()) -> 0()
   2: +(s(x1),x2) -> s(+(x1,x2))
   3: +(x3,s(x4)) -> s(+(x4,x3))

unjoinable peak
    s(s(+(x12,x1)))
*<- +(s(x1),s(x12)) ->*
    s(s(+(x1,x12)))