I agree with what you're saying but my comments were more aimed at the point before contracts are finalised. ie, customer says I want this type of material, contractor/architect state that that isn't suitable for the purpose and these are the pitfalls, client recites the adage 'customer is...
I'm no expert but if I as a customer chose something then I would expect the experts to advise if it is practicable or not for the purpose I want it for. If they do and point out the potential problems and then there are problems then that is on my head. If they don't and there are problems I...