I think to be fair to Roo here, her motives are completely different to those that she had throughout the rest of the season. I don't quite know whether to say it's selfless, but they're definitely not selfish such as the deceit and dirty tricks she played throughout the season.
If I am correct, Matt is now here for the next 700 episodes, where we still can't remember a single storyline he is involved in. Bizarrely with his premature apppearnance on the credits earlier this year, it's mid-1990 by the time he gets back on them.
Oh, and it did have the completely and utterly bizarre appearance of Floss and Neville at the school prom. At least though, there was a reason for them being there, unlike in later years when the entire town seemed to go along to them.