At the same time, he was registering companies from an address in leafy Remuera, but anyone who checked his or his wife's enrolment would have found them "residing" in Helensville.
It's not true that few people will care that Yule hasn't chosen to reside in the Tukituki electorate.
Sir John clearly thought it was so vital the he appear as a "local" that he purchased, furnished and enrolled at a property he almost certainly never lived in to maintain that appearance.
Key was right and his actions are backed up by solid research.
The Helensville electorate was, at the time, much more rural than it is now courtesy of Auckland's rapid growth, and the polling Key undoubtedly commissioned at the time would have shown a strong preference for a locally based representative.
Big-city voters know that boundaries change over time and are much more tolerant of an absentee MP, but regional voters like those in the Tukituki electorate expect their MP to make the effort and move into their electorate.
If Yule takes my advice and follows the example of Sir John, it's not too late to make a move.
Buying a house in Havelock North would be a vote of confidence in the measures taken by the Hastings District Council to clean up the water supply after the poisoning disaster but it might reopen some old wounds, however he could pick up a nice place in Flaxmere at a very attractive price.
There's a "freshly renovated, little cutie" fully fenced on a private site for offers over $159,000 on the market right now.
That's not even a year's salary for a Member of Parliament and he'd kick himself if Anna Lorck pipped him by a vote or two on September 23.
This is not an entirely flippant suggestion, as evidenced by the fact that high-ups in the National Party hierarchy are clearly fretting about Yule's ability to hold on to the electorate.
One of the complaints to the Advertising Standards Authority about Lorck's now amended billboards was lodged by Aucklander Cameron Slater, son of former National Party president John Slater and a right-wing attack dog let loose only when things look grim.
The only possible reason for Cameron Slater's interest in Tukituki is that the National Party has got wind of a problem and, given the polls, that problem is unlikely to be with the party vote.
The National Party locally and at HQ will also be concerned that water seems likely to remain both a local and a national issue this election.
The continued chlorination of the Hawke's Bay water supplies is still ruffling feathers, though Aucklanders who have put up with this for years have difficulty understanding the problem.
Giving pure artesian water away for overseas-owned bottlers to export at huge profits is an issue that has been placed firmly in the "too hard basket" by the National-led Government and is therefore an issue that can be exploited by the opposition.
If Labour hasn't changed its policy since 2014, a Labour-led Government would put a price on all large commercial water takes, with some of the resulting cash-flow going to the regional councils.
It seems loopy to me that Napier ratepayers are copping the cost of their own smelly water but "Pure" in recent years got consent to take 400 million litres of pure artesian water at Awatoto.
The Government of Fiji bills water bottlers a royalty of 15 cents per litre.
Why don't we do likewise?
• Mike Williams grew up in Hawke's Bay. He is chief executive of the NZ Howard League and a former Labour Party president. All opinions are his and not those of Hawke's Bay Today.
