Keyless entry car thefts

I read an article in the Times the other day that I thought might be worth sharing. It seems that car thieves have developed a method of stealing your car, if it's keyless entry, without stealing your keys. I don't pretend to understand how they do it, but it involves two easily obtainable radio transmitter/receivers. The next day a letter to the editor suggested a possible defence. Apparently if you put your keys in a tin box lined with tin foil radio waves cannot penetrate.

I've found a small tin which just fits our keys, lined it with tin foil ,and whenever we're not using the keys they'll stay in there.🤞