The phrase "I know it like the back of my hand" is one often used to indicate that the speaker knows something very well, indeed, but one man, this weekend, had to re-evaluate his use of it, when he realized he didn't really know the back of his hand very well at all.
Moys Kenwood, 56, was talking to his friend, on the phone, when the latter asked:
"Are you familiar with Bangkok?"
"Bangkok? I know it like the back of my hand!"
As he spoke the words, he glanced at the back of his hand. He frowned to himself. The arteries seemed to be more pronounced than he had hitherto noticed. His bony knuckles appeared to protrude more than they once had. The skin looked withered, and gnarled, and a darker shade than he remembered - he saw that he didn't really know the back of his hand very well at all.
Indeed, it could easily have been somebody else's hand!
He decided, right there and then, to stop using the stupid phrase, and just say "Yes" instead.