In regards of razor sharp skill

[shamino]

I was wondering how exactly razor sharp/sharpness works in this game, in all the MH Ive played so far its usefulness boils down into bestowing a chance of ignoring sharpness loss per hit. But Im not entirely sure It has the same purpose here, I wanna know because Im pondering whether is actually worth on Dual Blades.

[josek13]

This come from the wiki of MH2 about 'Sharpness':

Blunt increases the amount of sharpness lost while attacking and when blocking with the Great Sword. Sharp Sword reduces sharpness loss when bouncing to the normal amount, reduces sharpness loss when blocking with the Great Sword, and reduces sharpness loss for the Gunlance when firing Shells and Wyvernfire. Normal and Wide shells reduce only one hit of sharpness, Long two hits, Wyvernfire five.

From what I understand it seems a very good ability for the gunlance, for the rest I see it quite useless.