Spoiler That trip had a few good cuts in it to symbolise time moving forward as well as the fact that they pumped the instructions on how to use the ring right into his brain when he got there I think he had a decent grasp of how to use it to his advantage. I think the main reason they train in this universe of the film is to refine the skills they gain in the induction process. Kinda like the Matrix and their data download of skills but Neo had to refine his skills once he learned them. But I think there was enough of Hal as GL in it to justify it, Batman Begins didnt exactly have Bale in the suit the entire length of the film. Neither did thor.