sorry for being a retard on these types of builds, but i will flap my jaws anyway.
c4 and dynamite usage are suicide tactics. (i think)
grenadiers try to not die. (i know)
i could see a -ap or extended range, critical chance or accuracy modifier on a crafted grenade.
being a crafter myself, i would have to build a shit load of grenades to get a pile with the special modifiers that folks would want to buy.
just my 2 cents of jaw flapping.