Who Mourns for Morn? suffers a great deal from its place in the sixth season.
Who Mourns for Morn? is the second broad comedy in the last three episodes. It is the third light-hearted episode of the last six. That would be a lot of comedy for any season of Star Trek, but it is particularly apparent in the context of the sixth season of Star Trek: Deep Space Nine. After all, there is supposed to be a war raging in the background. The cathartic release of You Are Cordially Invited made a great deal of sense after the opening six-episode arc, and The Magnificent Ferengi was a brilliant comedy episode. However, this is just too much.
To be fair, the structure of the season contributes to this sense of humour fatigue. The decision to open the sixth season with a six-episode arc focusing on the retaking of Deep Space Nine was bold and ambitious, but it left little room for comedy or humour. As a result, the comedy episodes were concentrated in the aftermath of that sprawling war story, making for a particularly jarring contrast. The first half of the sixth season of Deep Space Nine only has three comedy episode, which is not too much by any measure. However, they arrive in rapid succession.
Taken on its own terms, Who Mourns for Morn? is a solid and enjoyable episode. It is not as funny as House of Quark or Little Green Men, but it moves quickly and works from a clever premise. It is populated with quirky supporting characters, none of whom outstay their welcome. Who Mourns for Morn? is a fun little runaround. Unfortunately, it arrives at a point in the season where the audience is exhausted from all those runarounds.