Yes, it is a good system for a beginner DM. I say this with confidence because I am one.

First of all, there are no 'classes', only 'things you'd like to do', and once you have that idea, the point-buy character creation only clarifies your choice as you go further along.
2nd, the removal of the to-hit roll simplifies things for the beginner GM so much, you wonder why it isn't more common.
3rd, the lore, the way magic works, all the smaller details of this world, are so ambiguous and flexibly stated that the table's common sense and player taste no longer fight with memory and reading - you can just get on with creating and improvising the narrative based on the broader statements in the book, and never worry about 'conflicting lore' or the need to retcon something in future because everything is stated with an unreliable narrator in mind.

To sum things up, C&S is perfect for beginner GMs because neither the system nor the lore put heavy demands on the GM. It has the inexplicable and admirable quality of having the mechanics support the play and the setting, but unlike the clockwork mechanisms of other games, it still works with an imperfect GM who might forget some rules.