In his latest column, PDC Stats Analyst Christopher Kempf analyses the sport's most impressive and consistent scorers, and evaluates how their ratio of three-treble visits and trebleless visits impact their results.
So long as a player is hitting trebles, it doesn't matter how they are grouped within visits.
Just as a player who suffers through a large number of trebleless visits could be redeemed by hitting lots of 140s and 180s in his other scoring visits, racking up the maxima can represent a futile scoring effort if the remaining visits result in many scores of 60 and 100.
But in practice, a player's ability to group darts tightly enough to max out their score, and to switch effectively enough to avoid scoring 57 and 58, is correlated broadly with overall accuracy on trebles.
Darts fans are now accustomed to seeing statistics regarding players' trebleless visits and 180s, but what about the relationship between the two?
Neither statistic alone tells the whole story of a player's scoring effectiveness. Consider players at two different extremes of the distribution with similar maximum rates: Joshua Richardson (0.238 three-treble visits per leg) and Krzysztof Ratajski (0.241).
Ratajski is far more likely than most darts players to attempt and hit 'alternative maximum' scores of 171, 174 and 177.
This is because he less frequently takes advantage of the benefits of three darts tightly grouped within the same target, therefore he cannot match the three-treble output of darts' 180 elite.
However, Ratajski is extremely disciplined when he doesn't have a big score; he is one of only six Tour Card Holders in 2025 who has averaged less than one trebleless visit per leg.
Richardson, despite throwing maxima at almost the same rate as a repeat ProTour title winner, has twice as many trebleless visits relative to his three-treble frequency.
Yet even though Ratajski's ratio is far more favourable than Richardson's, both players remain far behind the treble-shooting effectiveness of the PDC's reigning elite.
Every 2025 Premier League participant has one of the PDC's 15 highest ratios of three-treble to no-treble visits, but only Littler makes the top five.
Littler lands 0.53 maxima (almost always 180s) for every trebleless visit, making him the only player in the PDC with fewer than two visits of 60 (and similar) on average for every big score.
Though he has played 200 more legs in 2025 than Kevin Doets, he has fewer trebleless visits than a recent alumni of the Development Tour, and though he has played 1.6 times as many legs as another player close to him in age - Sebastian Bialecki - he has almost 5 times as many 180s to his credit.
The gap between Littler's ratio and the second place player is wider than the gap separating 2nd place from 12th.
Even if Littler was very inaccurate on his checkouts, he would be hitting trebles so often as to earn enough extra double attempts to win most legs anyway; but he is not, and the darts world is struggling to adapt to his talent.
In his 118 average tour-de-force in last week's Premier League, Luke Humphries had 18 successive visits of three treble attempts in which at least one dart found its target.
The average PDC Pro Tour player would expect to have 7 trebleless visits in that span, but Humphries leads the way for professional darts players in his ability to avoid scores of 60, 41, 45, etc., having had only 616 such in 659 legs.
Only one scoring visit of 26 has blemished Humphries' record this year; even the mighty Littler has six.
Though Humphries might be more ruthless and consistent than any other player in this respect, he lags well behind Littler (and others) in output of trebles.
No player could possibly throw few enough trebleless visits to compensate for that deficit created by the best 180 hitter yet seen in professional darts.
Apart from Littler, who in 2025 is accomplishing the extraordinary feat of leaving a finish after nine darts thrown in the majority of his legs, only one other player - Josh Rock - comes close.
Were it not for this teenaged usurper, the darts world would be marvelling at Rock's output of 0.484 three-treble visits per leg, and his ratio of 0.44 maxima per trebleless visit.
These figures leave him on an average score of 172 after nine darts, more than 15 points closer to checkout than any other player from the island of Ireland.
Luke Littler is winning nearly 80% of his matches in 2025 because no one hits trebles more consistently in groups of three, and almost nobody has a scoring visit less often without a treble.
This results in the fact that in most matches he plays, Littler scores heavily enough to earn for himself at least one additional double per leg than his opponent.
And as those opponents know, it's no great point of pride to have hit 100% of one's doubles if the denominator of that doubles fraction is 1.
Follow Christopher on Twitter @ochepedia