The pitching staff will be in a much better position to win. I believe i got in a long heated debate about this a few weeks back with another poster in a thread discussing "K sleepers".
I only used Mulders win total to highlight how very little the overral ERA correlates with the actual amount of wins. I think mulder ranked pretty high last season on run support, he was still able to win 5 games with an ERA over 6 after the break
The bullpen is stacked with very good 2-3 inning type relief pitchers. (Think Yabu, Juan Cruz, & Justin Duke)
Beanes new "philosophy" is working from the back-on-up. (its a cheaper way to get good/effective pitching) In interviews ive read, his plan is to only count on Meyer/Blanton for 5 innings -- you can bank on one thing -- these two wont be breaking the 90pitch bench mark to often, as this team advocates pitcher abuse points as strongly as any. (atleast untill their last years of arbitration where beane milks there arms for everything their worth before he ships them off) IE: Mulder / Hudson last season. (think of all the innings pitched the "big 3" have over the last 3 years)
Haren and Harden will get full/regular "workload". while meyer and blanton will be "babied" into the rotation (atleast this season) on a short leash....that is ofcourse if blanton even beats out Yabu and Etherton for the last spot on the rotation.
as far as the bullpens "effectiveness" or lack there of last year, i believe they were ranked last with the Indians for the most blown saves & holds. i think the converted save % was less then 60%. Calero, Yabu, Duke, Rincon, Bradford, Cruz, and Dotel wont let that happen this year. Rincon can go back to his LHP specialist duty and the rest of the rotation will be playing in their "roles"
Also from what ive read, expect dotel to not get to many 8 inning appearences, as he's stated clearly he wants to be exclusive to the 9th inning...Macha agree's and will use Dotel accordingly. He can afford to this season because of the bullpen depth acquired from the trades. (fantasy implications: those regular handfull of wins that A's closers get should dip some this season because of it)