I'm not advocating we go looking for a draw, but with a two legged semi final we know the formula that works.
Trying to park the bus I think is counter productive because a good side (and City are a very good side despite people missing right now) are always likely to find a way through or capitalize on a mistake. However I do think we have to look at this game in terms of don't loose.
To me that means strong and organized in the back like we've been, so as you say the back 4 pick itself. But it also means playing the counter attack so we've got to have pace in the side. For me that means Gerrard, Bellamy, Downing and Henderson. I might consider a punt on Shelvey as he also has pace, and based on his Blackpool record a heck of a long shot also, but I'd rather Henderson as he seems that much more mature and calm on the ball, and I'm convinced he's improving each time I see him, so think he's due a break out game.
I would go with the same defence we had against Oldham. It would not be fair on the fringe players like Carragher and Coates who have taken us this far to suddenly say, "thanks guys, you have managed to get us this far, but you will have to make way now". Cup games are currently their only means to get playing time and they have worked very hard to ensure they extend that playing time by defending very well to ensure our progress.