Welcome to the site, oburton88!
I'd agree with LilMaibe on the first question. Lot's of people travel on the Discworld, but no one (it seems) has ever travelled just for the sake of it.
I'm struggling to remember the bit about the Magnox reactor.
But there's this bit from the annotations on LSpace.org
- [p. 172/149] "[...] a specialist in the breakaway oxidation phenomena of certain nuclear reactors."
"Breakaway oxidation phenomena" is a reasonably well-known example of doubletalk. Basically, what Terry's saying here is that Dr Rjinswand is an expert on uncontrolled fires in nuclear reactors. And we all know what Terry's job was before he became a Famous Author...
Terry's job, in case you didn't know was Press Officer for the Central Electricity Generating Board in an area which covered three nuclear power stations.
“Men never commit evil so fully and joyfully as when they do it for religious convictions.” – Blaise Pascal