May 12, 2008 - Does David Cook have to watch his back now that David Archuleta's father has been banned from the set?  Did Jason Castro psychologically flub his lines, or was he undone by unwillingness to knuckle under the "Idol" machinery? And, seriously, how has Syesha Mercado managed to survive and flummox the critics?

As "American Idol" careens to its crowning moment, many questions arise. Of course, the…