That is a great article that you have researched from The Guardian, and I would think it reflects the general attitude and thoughts of the overwhelming majority of GPs?
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But when at the end it says it is "intended as an honest reflection of a typical long-term sickness case", it's likely to add fuel to the fire of public opinion that people on long-term sickness benefits are actually capable of work but would rather not, unless they can get just the type of work they want.