Some additional comments on some of these:
Short Fuse not giving its effect when Grenadier is traited
Short Fuse doesn’t work at all in sPvP. I haven’t had any problems with it in PvE or WvW.
Forceful Explosives doesn’t show the radius change on skill tooltips.
I always assumed this trait actually increased the damage radius for each individual grenade. I would guess that if this skill increased the radius(thus, effecting the tooltip/reticle) then it essentially just spread out the grenade cluster?