Genuine thanks to all who've sacrificed their time and/or effort to reply to my initial post. The response has been informative and sagacious, yet unpretentious, and quite frankly beyond all expectations - believe me, you's have all warmed my cockles!
Tbh tho, the only reason I posted this "paradox", which has indeed troubled my inquisitive mind since 1984, was coz I'd fallen out with my wife and duly dismissed to the "huffy room" with no Sky TV, no DVD player and no supper - BUT WITH WiFi!!
Thence I decided to try to rid my thicko brain of the conundrums she finds most perplexing, my initial post was the first one of myriad others!
Maybe I should just stick to assessing/diagnosing/ and solving plumbing and heating problems in future, eh?