not at all
You get an outlap, a flying lap, then an in lap with an instructor. Then you join a bus stop style Queue for another car to go out in.
There are no dual controls, no rev limiters, no limtis on speed. Just the knowledge that if you arse about, they'll bring you in and throw you out. So do as the instructors tell you and drive sensibly. Overtaking is allowed providing the other instructor waves you across (they are very good about doing this and can see when a faster driver is behind)
Top tip, go for one of the least popular and older cars (eg the astra VXR) and you need never queue. Last year everybody ran for the VXR8s, this year it will be the insignia VXR. I had the same instructor none stop for 45 minutes last year. Each time we came in, there was nobody queuring and about 4 or 5 astras sat doing nothing. So we went back out again. In the end we didnt bother comming up and just went round and round. I learnt a hell of a lot about the lines, and track driving and really improved the smoothness of my laps. Was excellent fun.
Then went and drove the VXR8, when it was much quieter towards the end of the session

Didnt bother with the Corsa or the Zafira.