I'm sorry clone_wolf, but you are completely wrong with it being in there only in the theatrical release prior to ANH being added. It wasn't and there is physical proof with the 1977 bootleg of star wars. You also need to listen to the commentary again because NOWHERE does Burtt mention that in ANH luke initially misses. here's what Burrt says:

We had at one time a scene where Obi-Wan and Padme fire a wire across an abyss and swing across together. It very much recalls the fun of the first Star Wars. And they were quite charming in the scene, 'cause she had to hang onto him. He had trouble getting the cable across. It kinda bounces off the first time and he has to reel it in and shoot a second time and she's kinda like, you know, "Jedi, huh?"

He's talking about the Obi-Wan/Padme scene and NOT the original star wars scene with Luke and Leia.

I'm also one of the "old farts" that saw it countless times in 1977 and that scene was never in there. At 10 years old i saw it so many times that i could recite the script word for word. I was also given a bootleg VHS the following year and there was nothing different in the chasm scene. The only differences were the lines of dialogue between the monomix and the stereo mix, and these differences were in there in 1977 and not changed when they added the A New Hope title.

There is also proof with the musical score. There is no section that this could be placed

And if that interview ever existed with Lucas admitting that scene was originally in the film on such a national talk show then some proof of this would have emerged by now, but it hasn't.