I'm hoping this is tongue in cheek, but as a physician, I do find this a bit insulting. Most doctors (even ones in harley street -- although anyone can hire a room in harley street, and there are a number of quacks there, I do admit) would not sign off on something merely for a cash payment. Some may do so out of sympathy, or err on the side of being 'nice' to a patient if the indication is borderline.

tb