IMHO I think you do have to change the team on a weekly basis, but what I would say is, maybe only one position.
I agree with Stu to a certain extent (and that doesn't happen very often), not only the speed of the games but the amount we have to play this year (its almost a blessing to be out of the League Cup) will take its toll on the team. Our season started before most othe teams in the EPL and normally any teams who do start that much earlier crash around Xmas. I think Benitez is aware of this and has tried to give all his players a break to ensure the batteries last longer into the tail end of the season where a league or champions league place can be won or lost.
I have been saying for a long time now, the team as a whole is not performing that bad. Ok the results haven't been going our way, but that is mainly down to us not converting the many chances we are creating week in and week out.
For me Morientes is improving with every game he has played since coming back from injury. Im not sure about Cisse and Crouch but only time will tell with them. What ever you think of our forwards there is not a lot Raffa can do with them until the transfer window opens, and Cisse may leave us and be replaced by someone else. Or it might be that, like all strikers do, they are all going through a rough patch.
Once we start converting chances you will see a rise up the table, win our games in hand and suddenly we are up there with the Man Utds and Arsenals.... Crisis over!