Continuity mistake: Phil sustains injuries to his face more than once in the movie. Every time the injuries disappear by the next scene. In one case the injury switches from the right side of his face to the left side between shots in the same scene.
Continuity mistake: When Will Ferrell is Giving the team a finch each, it shows all the players getting a cage, but when the camera angle goes back to Will Ferrell, the box of cages is full again.
Continuity mistake: When Will's dad has thrown all his darts, he grabs the darts off the board and he and Will begin to chat. The dad throws one dart at the board again, but in the next shot there are two darts on it rather than one.
Continuity mistake: During the tetherball scene, Will Ferrell's shirt tails keep changing back and forth between tucked in and hanging out.
Continuity mistake: In the scene where Phil and his wife are in the bedroom after Phil accidentally gets hit by Ditka, Phil's wife leads him to the bed and begins to rub his shoulders, then it cuts to the front of Phil and his wife's arms are down around his waist.
Continuity mistake: In the car at the beginning of the movie, when Phil is talking to his wife the tag on his shirt is sticking out. In the following shots the tag is tucked in.
Continuity mistake: Mike Ditka sets his coffee cup on the counter during the first butcher shop scene. When the camera angle changes, the cup is back in his hand without time for him to have picked it up again.
Continuity mistake: In the scene where the mom puts sun screen during one of the games, every tine the switch angles the cream is different.
Continuity mistake: Introduction of the various Tiger players. Hunter holds the worm leaving its head free to squirm and wriggle in the wider angles, but the head is not sticking out in the close-up. (00:20:20)
Continuity mistake: In the first scene with Mike Ditka, he is arguing with Phil's dad on the opposite ends of a wall. Ditka's arm is positioned on the wall in a way ever-changing between shots. (00:07:15)
Answer: An actual dervish (not derbish) is a member of any of various Muslim ascetic orders, some of which perform whirling dances and vigorous chanting as acts of ecstatic devotion (hence the term "whirling dervish"), though in general 'a whirling dervish' is used for anyone who moves with an unfocused, almost frenzied energy.
Xofer