Merlin fanfiction that deals with him being overworked often circles back to the show's core dynamic: Arthur’s obliviousness and Merlin’s hidden burdens. The exploration isn't just about him taking a day off. It's about the breaking point forcing his magic, or his identity, into the open in ways he can't control. A servant with that much power and responsibility has no real outlet, so writers create them.
I've seen a few common patterns. One is through injury or illness – a magical exhaustion trope where he collapses, and Arthur (or Gaius) has to confront the sheer scale of what Merlin does. The stress relief comes through forced rest and the subsequent care, often leading to a shift in their relationship. It’s a catalyst for emotional payoff.
Another angle is through darker coping mechanisms. Fics where he uses magic for small, selfish comforts, or even lashes out magically in frustration, which I find more psychologically interesting than the pure hurt/comfort route. It highlights the isolation. The relief, when it comes, is messier. Sometimes the resolution isn't Arthur finding out, but Merlin finding a private, magical sanctuary, which feels true to his character’s secretive nature.
Ultimately, these stories work because they address a tension the show always played with but rarely resolved. They give Merlin a vulnerability he was denied, and the 'relief' is the narrative finally acknowledging the weight he carries.