When Marge asks if Bart could drive the car, he says it’s his first time which is an obvious lie which is why he pulls out a key and driving gloves. Bart had a driver's license and drove in "Bart on The Road"; everyone in the family knew this except for Marge. Bart also drove in "Burns' Heir", "Bart Carny" and "The War of the Simpsons" before this episode.
In Viva Ned Flanders, Homer tries to get Ned to accept being a polygamist on the basis that having two wives can be great. Homer imagines himself lazing in a hammock while Marge and Amber do yard work. This episode is far different, where Marge is clearly unaccepting of having Amber in the house. This once again shows how reality is often far different from Homer's fantasies.
As Marge and Homer's marriage from the episode 'A Milhouse Divided' was void, this meant that Homer's marriage to Amber in 'Viva Ned Flanders' was not bigamous.