[Sting 11]

I'll add that the controller was probably also working approach/departure control as well, and could have been looking at the radar scope, pulling flight strips off of the printer...anything really.

Provided the runway ends are visible from the tower, I personally would get a visual confirmation that everything appears OK with my departing aircraft. I can't judge this controllers actions, though, with limited information.

[El Gato]

Provided the runway ends are visible from the tower

If you look at the airport diagram you can see that the tower is ideally sited for observing aircraft in the departure area of both 22 and 26.