A pretty enjoyable pair of episodes and a good story all round. As it says in the intro, this is one of the Doctor’s great ‘oops’ moments – his original quick fix turns out to be the entire problem.
When Xoanon is imprinted with the Doctor’s personality over his own, guess what form his resulting madness takes? Hint: both the Tesh and the Sevvateem worship Xoanon as a god.
Yes, the Doctor’s God Complex dates back to BG Who. 🙂
The Sevvateem’s deeply argumentative nature turns out to have been bred into them: the Tesh are into control of emotion and devoted obedience. All things considered, it’s faintly unsurprising that not only does the Doctor do a runner as fast as possible, Leela decides to come along as well.