I understand that The Simpsons have been on television for a very, very long time. I also understand that this is animated series and the characters do not age. This, of course, messes with the timelines and back-stories established by the series. Although these people are frozen at their current ages, the years are moving forward around them. Basically, anything that occurred "five years ago" in season two happened in 1988. Today, if the show refers to events from five years ago, they're talking about 2003. But the timeframe of events can be largely overlooked if two things remain consistent: the stories stay true to the characters, and the episodes are funny.
Unfortunately, "Dangerous Curves" just wasn't all that funny. As for staying true to the characters, it could have been worse. Personally, there haven't been many recent flashback episodes that I have enjoyed. The first ten or so seasons of The Simpsons did a fantastic job of establishing the Simpson family back-story. Episodes looking back from this era successfully stuck close to that reality. The latest flashback episodes, however, have changed a number of ideas. Last season's "That 90's Show" really irked me by establishing that Marge broke up with Homer and attended college before getting knocked up with Bart. That information changed the way I viewed Marge. She was no longer the innocent girl who fell for a boy, got pregnant before getting married and struggled to make it all work. "Dangerous Curves" doesn't do that type of damage, but it does throw near-infidelity into Homer and Marge's life.
"Dangerous Curves" was crass, cold and seriously lacked laughs. The situations were very forced and the timing was incredibly hurried. All that said, I did find Bart and Lisa as the bickering couple in the pedal car to be very funny. It added a fresh twist to this generally stale outing. And, of course, there were other fun laughs, including Alberto's 45 minutes of silence to complete his "Or should I say 'glide'" statement and Ned Flanders' quip about Homer's "single entendre." But none of that could make up for the poor story being told or the overall unfunniness of the episode. And did the writers of this episode really think that a "Cereal Killer" video game was an original and hilarious idea? That was just lazy, lazy filler.