Having said that, I think Rory Stewart has a good grasp of government procedures and politics, including economics.
I find it rather sad when people start to be destructive about other people's degrees. Degrees, after all, only mark a level at which you can learn. After that learning becomes much more diverse.
Whatever Stewart is or isn't, the one thing he has shown is an ability to dissect, analyse and learn. This has been rewarded by a number of international awards for his writing. He has also received an honorary doctorate from the University of Stirling. In 2004, he was awarded the Order of the British Empire and became a Fellow of the Carr Centre at Harvard University. It seems to me that he hasn't stopped learning. That openness to new knowledge seems to be something lacking in many, including many politicians.
The series of interviews under "The Rest is Politics" logo is called The Rest is Politics - Leading". In them, unsurprisingly, they manage to interview leaders, often those who rarely if ever speak in public. Both interviewers seem able to discuss from different points of knowledge and draw out the interviewee.
There is another group of videos called "The Rest is Politics - Question Time", where they answer listener's questions. Recently a listener asked what Rory thought of the fast-track system in the Civil Service. Listening to him describe what he thought, it seemed obvious his thirst for learning is not yet dead.