The science in the episode is very weak -- evolution doesn't have any predetermined outcome -- but then, that's par for the course with Trek's approach to biology. Setting that aside, though, whether a story is good or not shouldn't depend on whether or not you agree with its characters' choices. On the contrary, often in good stories, we're supposed
to question or doubt the characters' choices. I don't think Sisko made the right choices in "In the Pale Moonlight," but it's still a very powerful episode. I didn't like Kirk's decision to arm the natives in "A Private Little War," but I admire the show for daring to do an episode that wasn't about perfect heroes making black-and-white choices.
And the same is true here. I don't really agree with the decisions Phlox and Archer made, but that's beside the point. What matters is that "Dear Doctor" is a challenging, powerful, character-driven episode, and it deserves recognition as one of Star Trek
's finest hours. It's something very rare in the franchise's history -- a pure drama, a story where all the conflict and tension come from character interaction and moral dilemmas, without any tacked-on violence or danger to meet some arbitrary quota for action. One thing I admire about the first season of Enterprise
is how its producers tried to go for a more intimate, character-driven, dramatic approach than previous series, and "Dear Doctor" is perhaps the pinnacle of that. I have my quibbles with its science and the ethical choices the characters make, but those quibbles don't cancel out everything I love about the episode. It's well-written overall, it's well-acted, it's got a very good musical score, and it raises some interesting, if conceptually flawed, moral and philosophical questions.