So the belly putter has belly flopped.

The broom handle has been brushed away. As of January 1, 2016, there will be no more different strokes for different folks, the Royal & Ancient Golf Club of St Andrews and the United States Golf Association having decreed that long putters will be removed from the game of golf on that date, thereafter to languish for all time at the back of the garden shed or in increasingly desperate adverts on Gumtree.

Actually, they didn't say that at all. What the R&A and USGA really announced was that players will no longer be allowed to use any part of their body as an "anchor point" when making a stroke.

Concerned that broom-handle and belly putters were taking something fundamental out of the game, the two organisations moved swiftly and decisively, taking, oh, only about 25 years to reach this firm conclusion.

In which time, of course, millions of the things have already been sold. Back in the late 1980s, when he still looked like some sort of Ayrshire version of Borat, Sam Torrance's sudden adoption of the long putter would scarcely have provoked more comments if he had been stalking the greens with a Jedi lightsabre instead. Since then, however, they have become almost commonplace – long putters, that is, not lightsabers – which begs the question why golf's rulers have only got round to dealing with them now.

The answer lies in the fact that some seriously good golfers started winning some serious amounts of money with the things. With apologies to the noble exception that is Mr S Torrance of Largs, the vast majority of long putters, whether of the belly or broom variety, were used by players who, not to put too fine a point on it, were getting on a bit. They were a way of breathing new life into a putting stroke that, perhaps mirroring other areas in their lives, had gone a bit floppy. A long putter was as much a rite of passage into middle age as nostril hair, visits to garden centres and humming along with Classic FM.

But when younger golfers started winning significant tournaments with long putters, the authorities' eyebrows started to rise. And they went into orbit when, in quick succession, Keegan Bradley, Webb Simpson and Ernie Els long-putted their way to major championships.

When 14-year-old Chinese prodigy Guan Tian-lang secured his place in the Masters field last month by winning the Asia-Pacific Amateur Championship with a belly putter, the aghast expressions in the R&A clubhouse were worthy of a Bateman cartoon entitled "The Man Who Broke Wind During the Lady Captain's Loyal Toast". Which is why the game's rulers put an end to a quarter-century of pussyfooting, shilly-shallying and thumb-twiddling on the issue and announced their imminent ban.

Well, imminent by their sloth-like standards, but let's not get bogged down in that issue. The deed is done, the ruling made. As of January 2016, there can be no possible room for doubt on the matter.

At least that's what the decision-makers told us last week. Their new rule (14-1b if you must know) says: "In making a stroke, a player must not anchor the club, either directly or by use of an anchor point." Helpfully, they then add a couple of explanatory paragraphs on what this all means. Less helpful, though, is some of it is still as clear as mud.

In a funny kind of way, we all sort of know what they sort of mean. They don't want putters to be held against chins or tucked into abdomens, and nor do they want the hand nearer the butt end of the club to be made a fixed point by holding the forearm tight against the body. But golf is a game of absolutes and I have a creeping suspicion that the phrasing of the new rule leaves far too much scope for ambiguity. And that, in golf, always spells problems.

To their credit, the USGA issued a set of photographs to show what can and can't be done under rule 14-1b. But between that which is clearly legal and that which is emphatically not, there are still grey areas. The bracing of the forearm against the body is only the most obvious – how tight must the brace be to become an anchor point? – but it will surprise me not one bit if other issues and questions arise when the rule becomes active.

Personally, I find it hard to make my mind up on the matter of long putters. I'm persuaded by the argument that an anchored stroke is not a "real" golf stroke, but I can also see virtue in the fact that these soon-to-be banned implements can bring pleasure back into the game for many people. PGA Tour statistics also suggest that the benefits of using a long putter have been exaggerated.

But there is nothing to be said for a ruling that leaves things so vague and which, I fear, will lead to some messy disputes, and not just at the elite level, when it comes into force. The sport's rulers have tried to shut a stable door after the horse has cantered off into the distance. But they have left the thing creaking on its hinges.