Whenever I see a signed this or that for sale, I ask myself why anyone would want it. Apart from anything else, unless you were standing next to the celebrity when they wrote their name down, how can you know it’s genuine? With that in mind, I wish to vouch for the authenticity of one unique piece of memorabilia.

A friend, quite beside himself with mirth, has sent me details of lot 4238 in an auction next week. Though it was only a WhatsApp message, I swear I could discern the marks from the........

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