Yup, that was Yahoo! taking an active interest in my P slots on Sunday.
The "Roster Alerts" section of the fantasy home page was full of warnings about my pitching staff, because I'd benched everyone in a head-to-head league. That's just basic end-of-week strategy. Sometimes, you have to simply take a knee.
While there was a remote chance that I could have caught my opponent in wins if things had gone fantastically well (they didn't), there was also a decent chance that I could have lost ERA, WHIP, and K/BB. Benching all of my SPs, RPs and Ps essentially guaranteed a 4-3 edge in the pitching categories, and it allowed me to avoid CJ Wilson's brutal fantasy line:
0.0 IP, 0 W, 0 SV, 0 K, Inf ERA, Inf WHIP.
No, you don't want that. Better to just have the empty P slot and suffer the warnings.
If the risk is limited and the reward is significant -- let's say you lead 3-2, you're dominating the ratios, and you're only one win and five Ks away from 4-0-1 -- then you start everyone.
Otherwise, well...you hate to take points off the board.