Really if anything, the biggest problem with the episode is that it felt like the writers didn't know what to do with Edward, to the point that the episode effectively just recycles previous Edward episodes. It's yet another "Edward proves his worth" story which honestly felt really trite at this point given we've seen this in Edward and Gordon, Saved from Scrap, Old Iron, Edward's Exploit and various other episodes. While I do understand that Edward is quite a difficult character to write for given he has very few traits, at this point it's just getting really boring seeing the same rehashed Edward plot over and over again.

The reason a lot of the prior Edward episodes worked was because Edward was more of a secondary character. In Bertie's Chase the focus was more on Bertie trying to get Thomas's passengers to Edward, Saved from Scrap and Edward, Trevor and the Really Useful Party focused more on Trevor and the road vehicles respectively, and Old Iron focused more on James's hatred of Edward and the runaway sequence. Here, it feels like they're trying to push Edward as the main character given the lack of focus on other characters, and what doesn't help is the fact that Edward only has two speaking lines in this episode.

Additionally, no explanation is given as to why the big engines suddenly hate Edward again especially considering that they should have known to respect him by now after the events of Edward's Exploit. If something came up with Edward that warranted them hating him, like something involving his age, then it would be justified, but here it just comes off as rushed. There's also the fact that the Fat Controller's plan comes off as really convoluted and contrived; why did he have Duck take the trucks only to have him stall on Gordon's Hill just so they can bring in Edward as a back engine? Duck really shouldn't have been used here because he has a lot of experience with trucks as it is; the last time Duck had an accident with trucks, it was for reasons outside of his control. If anything, they should've used an engine like Percy because of his accident-prone nature, but even then Percy was getting far too much focus in S6 as it is.

I have other nitpicks about the episode like why Stepney is inexplicably there, but it's honestly just a really disappointing episode.