Doesn't even Wikipedia say to take Wikipedia with a large pinch of salt?
On Stonewall and legal advice, if they have used fully qualified lawyers to push their rubbish, then surely they have some sort of liability?
In my industry, (geological and hydrographic survey) all reports have a disclaimer that, whilst everything has been done by jolly clever, highly trained monkeys, if your oil rig sinks, its not our fault, on the grounds that all data is acquired via remote sensors and processed by humans, which may give duff results.
You really, really have to fuck things up, before a client will sue, even if it's lost them a few million.