The thing is, if Mousinho had been the one who left and Nelson had stayed and was playing well everyone would be wanting to come on here and say they never rated Mousinho, and sing Nelson's praises. Fans are very fickle and (naturally) want to put down players who've left, and big up what we have.
Fact is, Mousinho was dodgy as hell for us at times previously playing CB. That's just a fact. He was then moved into defensive central midfield and did much better, and was exactly what we needed there at the time. But, to his immense credit, he has returned to the back four and done really well, looked unrecognisable at times, so solid and comfortable on the ball. But that doesn't mean that we have to rewrite history! Lets not forget also that Nelson was brilliant at times for us, especially for example on the great run we had at the end of last season. He didn't go to the Championship for no reason.