NO

1 decompositions
 #0 -----------
   1: +(0(),y) -> y
   2: +(s(x),y) -> s(+(x,y))
   3: +(x,+(y,z)) -> +(+(x,y),z)

unjoinable peak
    +(_y10,_y12)
*<- +(_y10,+(0(),_y12)) ->*
    +(+(_y10,0()),_y12)