Both Cumberbatch and Tennant went on to achieve huge success in Sherlock and Doctor Who respectively, and now have dedicated female followings (note the Cumberbitches).
Moffat has spoken before about wanting actors who are "attractive in a very odd way" for Doctor Who.
"None of the Doctors are conventionally attractive but they're all arresting. Handsome men don't quite suit," he said earlier this month.
Elsewhere, Tennant is set to reprise his lead role as DI Alec Hardy in the second series of Broadchurch after making the US version, Gracepoint.
Cumberbatch has turned his attention to the big screen, starring in 12 Years a Slave, The Fifth Estate and the forthcoming The Imitation Game, in which he will play gay mathematic genius Alan Turing.
Fans can rest assured that a fourth series of Sherlock is in the pipeline for 2016, but Moffat is finding it tricky to pin down his popular actors.
"(Cumberbatch's fame) can be quite annoying too if you're scheduling a damn show," he said.
- Independent