This episode was built on a premise established in the Diamond and Pearl games; Elite 4 Flint asking the player character if he can cheer up Volkner, who is bored with weakling challengers to defeat.
The anime takes it up a notch by having Ash battle Flint, that same member of the Elite 4, in an attempt for Ash's "spark" to ignite Volkner so he can finally see battles like he used to.
Ash's performance in the battle, against an Elite 4 member, was almost a completely sweep. Pikachu was the only pokemon that was able to stand its ground for more than a minute against Flint's Infernape. The purpose being? Ash and Pikachu fighting against their opponent, never giving up and still fired up, being similar to Volkner's situation when he fought a pokemon poacher as a kid.
The dub tackled this episode head-on. I see no big errors in terms of the screenplay. I would have been glad that they retained more of the music, but at least they kept three important themes.