Loved all that especially as it started to incorporate the environment. It also led into the final build toward Battle of the Heroes. IMO the pacing was great, but also long enough to be satisfied by the final duel that had been promised for years. Perhaps I indulged in it as did Lucas, but I'm happy about that. Shame about some of that dialogue though.
While I can certainly understand the need/want to indulge in what is THE battle in the Star Wars Prequel Trilogy (as Luke vs Vader Pt. 2 is THE battle of the Original Trilogy), the problem that I have with the fight from a storytelling, narrative perspective is that there is no further escalation from the point where they clash, to the conclusion.
Some of the best action scenes (whether they be a fight scene, or a scene of great tension like the T-Rex Paddock attack in Jurassic Park), is that there is always a sense of progression and escalation of the conflict. Ironically enough, the Yoda/Palpatine fight that the Obi-Wan/Anakin fight is juxatposed with has better escalation.
An example I have of escalation in a well done action scene is the train battle between Spider-Man and Doc Ock in Spider-Man 2. Throughout that fight, there is great tension and escalation from the start of the fight to the end. Not much needs to be said between the two characters, because the action speaks for itself. The battle starts away from the city, atop a building, then they tumble down onto the train. From there, they fight atop the train as it speeds along the tracks, with Spider-Man narrowly avoiding hurting civilians as he jumps and flips and dodges low overhangs, passengers, and tentacles. As the fight progresses, Doc Ock becomes more desperate, and starts to fling passengers off the train. That's a point of escalation as well. Spider-Man has to contend with rescuing innocents, while still trying to stop Doc Ock.
He does that, and a flustered Ock disables the brakes on the train, causing further escalation, and Spidey has to decide if he wants to pursue Ock, or save the civilians. Naturally, he chooses to stop the train. Only to have the situation escalate further when he sees, thanks to his Spider Sense, that the train track comes to a drop off at the end that will no doubt kill everyone on board.
What makes that scene amazing isn't just the way it was shot, or how long it was, but the growing escalation between the the protagonist's goals, and the antagonist's goals, and how they attempt to achieve those goals while stopping the other person from achieving their goals.
The Anakin/Obi-Wan duel, loses some of that escalation around the time they dramatically clash against the lava backdrop. We know why the two are fighting, but eventually the tension just drains out of the fight once it moves from being personal, to some kind of over the top swinging on ropes, leaping off of falling bridges, and surfing on lava robots. It's not that it's silly, it's just that it's kind of flat after a while. It's like having a sensitive area get over-stimulated if you know what I mean. Eventually you get kind of numb to it. I feel that way about the Man of Steel action scenes. No stakes, no tension, no escalation = boring action scenes for me.
The beginning of the duel was fire and intensity. They were using everything they know about the Force and lightsabers to try and kill one another. All that jibba jabba at the start of the fight was, honestly, all you needed to establish the pain and frustration both parties felt at that moment. I wish that stuff could have been written better. There wasn't much need to have them have a heart to heart while surfing on lava. All that needed to be said was said. At that point in the battle, it was just, "One of us is going to die here. That's the only way this is ending."
It's unfortunate that we knew going into the battle that neither one of them was going to die, which added to that lack of tension and escalation. How the fight ended was weak, and kind of anti-climactic.
Having Obi-Wan and Anakin clash on the bridge, with the lava backdrop, both of them getting disarmed in the conflict, resulting in more fisticuffs, and have Obi-Wan get the upper hand of that battle, with Anakin falling presumably to his death on that bridge after some gritty fighting, with Obi-Wan picking up his fallen lightsaber, thinking his former friend and pupil were gone for good, could have preserved some of the tension, while still keeping the flow of escalation in tact.
The rest of the movie still could have played out the way it did. Padme dying, the twins being born, Palpatine finding a battered and ruined Anakin at the base of the fallen bridge, burned nearly beyond recognition, and only his rage and hatred keeping him alive. Obi-Wan wouldn't be seen as an asshole that didn't mercy kill his friend after he caught on fire and started being burned alive, etc.
Obi-Wan would not be 100% certain that Anakin was dead, until some point in the future, when he learns of Darth Vader's exploits eradicating the rest of the Jedi. At that point, he was too broken and distraught over his failure to save Anakin to pursue another confrontation with his friend.
I can't say that there is a sweet spot for action scene length, but I do feel that being mindful of flow of escalation and tension, and keeping that from flat-lining is important, and was missing in that latter half of the duel. It still would have been epic and intense had it ended sooner, and had a more satisfactory conclusion to Anakin losing the duel than "I have the high ground!" Overall, I still think that duel is one of the highlights of the prequel trilogy anyway.
