This could've been a solid 30-minute story, but due to the structure of broadcast TV, it was instead stretched to be 42 minutes. This is mostly felt in the tripping sequence and the denouement. Each one was drawn out to almost pain-staking proportions because that is what the studio called for. That's not to say it ruins the episode, but it does kill the pace at times, and even ventures into the avenue of over-explaining itself. Case in point: the final scene where Mulder and Scully walk along a road and openly talk about the themes of the episode. It didn't feel natural or a part of the story, rather a conversation you'd hear two friends have after the episode's broadcast.
Although, the episode length isn't the only issue in this script. Everything felt very on the nose. Most of the dialogue with the side characters was just blatantly "let's write people who are unequivocally in the wrong to help prove our point." It even steps the line into stereotyping at times, even though the story itself is a statement against that.
However, this episode does boast some huge positives. I can clearly see what the writers were trying to go for, and the balance between humor and the dark subject matter had good intentions. The power of suggestion plays a huge part in the episode, and the analogy between the antagonists' actions and the effects of the Mulder's pill was cleverly done. The Mulder and Scully doppelgangers, while not used to the extent they could've, mixed things up. They made the episode feel fresh. And that boat sequence is such a visual treat!
All in all, it's a stretched-out, dialogue-heavy mess, but it's built on a strong foundation. It's an enjoyable enough episode, but not one for repeat viewings.