Seems like alot of people are guilty of overlooking ratio categories during live (yahoo) drafts. What may seem like a good pitching staff could easily turn into a mediocre one with the addition of pitchers like Jeff Weaver, Kaz Ishii, Gilbert Meche to name a few. And on the hitting side you have your Adam Dunn, Pat Burrell and Tony Batista's of the world who could do alot of damage to your batting average. Luckily for pitchers whip & era are probably two of the more unpredictable stats, but people like Ishii are BB machines.
It is difficult to put together a good pitching staff (5x5) and do well in all 5 categories. If you stack up alot of SPs you are bound to do well in wins by sheer volume, but likely to suffer badly in era and whip. If you load up on good setup men and closers, you will kick butt in saves and probably era and whip as well, but will sorely lack in wins and Ks. Seems like you need to be careful when drafting SPs that you don't draft someone who is going to kill you in era and whip. That's why it's important to try to get 2 of the 4 tool SPs if at all possible, which is doable with a little luck and or incompetence by other fantasy owners. Then fill out the rest of your starting rotation with a few under the radar starters like Webb, Contreras, Santana, Pineiro, K.Wells etc...