If im not mistaken it was 38% increase at 80 cap, I am not sure.
And to everyone who is saying that its useless here is a scenario for all of you unexperienced people.
A Pure INT Spear PvPing a Pure INT S/S. The S/S Puts his Snowshield on but the Spear starts off with a Fan storm which would give him 15 sec of advantage at the end after the 2 min pot fight, and an extra 15 sec if he uses fan storm at the end too. If the S/S player uses the blocking ratio increase over the Phy damage increase 15 sec buff BEFORE snowshield, his chances of tanking the 15 sec before the Spear pops his snow are alot higher leading to an equal fight.
Think...

EDIT: Unless its some new 90 Cap skill you are discussing.