I really find it amusing that people believe that you can somehow make up for a weak lineup by selecting a decent no. 8. That doesn't help the team, they still will lose, probably just by 20 less runs. These guys are not specialist batsmen, that's why they are down the order. Would you trust a batsman who averages 30 as a backbone in your middle order? A batsman averages 30 for two reasons, talented but inconsistent or not that talented but a grinder. Adding another one at 8, in constant pressure situations wouldn't seem to be the best of solutions. In strong teams, matters even less.
That's my issue with the all-rounder obsession, if they are specialists, the second skill isn't an ATG or anything above competent level, yet it's made out to be that way. That's equally why I get frustrated when people criticize Hammond and Kallis. They say they didn't take enough wickets to qualify, but really the job is to provide relief and take the odd wicket, and not get carted around the park. Pollock, nor any of the bowling all rounders are taking on a great attack that just decimated your lineup and winning the match.
If your lineup isn't scoring runs, you have bigger problems, problems Pollock isn't solving at 8. Want to make a difference, get a bowler who may bowl out the opposition for less.