Taken on face value alone, this episode is of the highest quality, using the Flash's speed and powers to the max, along with finally giving us a good speedster teamup episode. The execution was at times the best the show has ever been, the tension and stakes kept high...except, of course, that this is a standalone concept episode that has no bearing on the plot itself. Thus, you already can predict the general plotline.
Also, as people pointed out, if Barry was this fast, then he'd be virtually unstoppable. The Thinker wouldn't even be able to get a thought out in time to stop him if this was his speed level. That's the problem, which means that the premise thar made this episode so great is also its greatest weakness.
Ultimately my enjoyment outweighs my disbelief, and I can forgive the one-off rule-breaking for an otherwise brilliant episode in a dull season.
Also, as people pointed out, if Barry was this fast, then he'd be virtually unstoppable. The Thinker wouldn't even be able to get a thought out in time to stop him if this was his speed level. That's the problem, which means that the premise thar made this episode so great is also its greatest weakness.
Ultimately my enjoyment outweighs my disbelief, and I can forgive the one-off rule-breaking for an otherwise brilliant episode in a dull season.