Well at lv246 cata i hardly use rush because of the sp cost and not being able to keep finestra up all the time is annoying however once u reach lv200 u never solo anymore because everything require a party.
If u group up a mob with a party and u cant finished off the mobs before a lv5 finestra expire then you have a terrible party.
That extra block and crit from higher lv finestra is nice as you get more stats point into str and con but frankly speaking if ur looking at finestra for more str/dmg than your playing the wrong tree. U should go wiz or archer tree for dmg. Use the spare points you managed to shave off from dex into con.
Now the extra block is fantastic but auto block is for situation where u miss or screw up the c block timing. Or ur just lazy to time it. However it wont really matter since c block is better than auto block and auto block is just there for mistakes even though having a high auto block rate would be perfect but to get it really high enough to make c block obsolete is impossible.
Now that you understand dmg, auto block only looks good on paper for swordman. You should roughly see the value of movement speed as its obvious game changer affix. You gather up mobs with swb then let your party kill it within 3sec. With higher hp pool u can withstand alot of hits and since ur in a party u dont need to worry about recovery. U have a healer for that.
during ET mob wave. Your job is to kite a train of mobs round and round luring them into the aoe attack zone of your team. Because you move so fast you dont get hit at all by melee dmg. And u cant dodge range magic attack so dex is usless. Only mdef gear stacking and con will help.