Scottish canyoneering and themes of risk on guided trips

See the link for insightful comments on a Scottish canyoneering case that went before the courts, courtesy of our colleagues at the Sports Law Canary blog (commentary here). It adds to the theme that is emerging in the last couple of posts here regarding exposure to risk on guided outings.

Considering this case and the heli ski and fly fishing articles below, it raises some questions.
What level of risk is appropriate in a guided setting? Should novice clients be allowed the same exposure as enthusiasts and trained participants? Ski instructors get this, as they take their beginners to the green runs. Paddling instructors teach basic skills in sheltered bays or on easy rivers. Guided participation trips though, like canyoneering, heli skiing, or rafting allow people access to terrain they clearly do not have the skills and experience for (hence they hire a guide). Is it that easy? What are the limits to assumed risk and informed consent when the client has zero experience with the environment? The courts often side with the freedom of choice argument (but not always), for adults at least. But realistically, at the extreme end of things at least, assumption of risk and informed consent, while legally binding, often turn out to be pretty hollow when things go wrong.