I don't know what's happened to Rooney Mincey but sticking him out on the left is basically saying to him 'you're shit, you're playing here as punishment'. It's hardly going to help the confidence issue. Fergie doing it doesn't justify Capello who clearly has no mind of his own doing it.
The problem is Capello doesn't have time to sit and wait for Rooney to find his best, high expectations come along with the England job. The media, fans and the FA want quick results and Capello is never going to stick Rooney up front when he isnt scoring. He's only scored 9 goals in 29 games this season. It could of been a 0-0 draw against Wales had Capello stuck Rooney up front.
Its the same with Ferguson, he's not gonna play Rooney up front every game if he isnt scoring... it could cost them the league. Luckily for United, while everyone was being ripped off across the league by spending over £25mil on strikers... they went and signed an underrated mexican for £8mil.