One mans cold start is another's normal start so there is no one fix fits all
Hmmm, I do not agree.... I think that in large measure here, the "men" involved is Mr. Lycoming, and/or Mr. Continental. Their requirements with respect to temperatures for starting have been clearly presented here, and are not in dispute.
As has also been said, conveinence, (or being on any particular island) does not absolve one of conforming as closely as possible to the manufacturer's recommended practices for preheating (or any other aspect of operation).
I agree that the UK does not have weather conditions which would ever make draining engine oil and taking it into your log cabin overnight necessary. but the temperature values below which effective preheat of the engine are required, are clear. It sounds like those do occur in the UK (I have certainly experienced them).
At a minimum, any owner can arrange for a plug in engine preheating system to be installed, buy a properly fitted engine blanket, and a 500W generator. Take the generator to the plane, fire it up, plug, in, come back a few hours later, and you'll be ready to go. I have done this many times, where electriciy was not available.
If this is too much trouble and expense, a much cheaper method is to preserve the engine properly, take the battery out, and fly it next spring. This is what I have done to my second aircraft, a Lycoming powered amphibian, which does not have cabin heat. It sits safely and attended to, but out of service for the season.
The manufacturers of aircraft expect you to take care of them with consideration to the recommended practices. If you choose otherwise, you are taking direct responsibility for the engine's condition in the long term.
If owners are going to develop their own practices with respect to care, operation and maintenance of aircraft, why do people like me go to all the effort to write flight manual supplements, and instructions for continued airworthiness for these aircraft?