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Shaft Fit Lab Reno, NV · 4,505 ft
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Fit the Spread, Not the Average

Two golfers with an identical average seven-iron can need completely different sets. The width of the pattern decides it, not the middle of it.

The average is the number people ask for. The spread is the number that decides how many clubs belong in the bag and how far apart they should sit.

Two golfers came through the bay in the same week last spring. Both averaged a fraction under 165 yards of carry with a seven-iron. On any summary screen they were the same golfer. They left with recommendations that had almost nothing in common.

The difference was in the shape of the sample, and it is the thing a single averaged figure is structurally incapable of telling you.

Eighteen swings each, extremes removed, same afternoon, same bay
Golfer Carry median Shortest Longest Spread
A, plays twice a week1651611709
B, plays twice a month16414817527

What a nine-yard spread lets you do

Golfer A can genuinely tell two adjacent clubs apart. If we space the set at ten or eleven yards, each club occupies a band that does not meaningfully overlap the one next to it. Tightening the gapping is worth doing for him, because tighter gaps mean more pins are reachable with a full swing, and a full swing is the most repeatable thing any amateur owns.

For him, the useful conversation is about the top of the bag — whether a long iron and a hybrid are duplicating a band — and about lofts being where the stamps claim they are.

What a twenty-seven-yard spread means

Golfer B's seven-iron covers a band from 148 to 175. His six-iron, spaced at a conventional eleven yards, covers roughly 159 to 186. Those two clubs overlap by sixteen yards. On a course, standing over a shot, he cannot reliably choose between them because the clubs themselves cannot reliably be told apart.

Tightening his gapping would be actively harmful. It adds clubs whose bands sit inside each other, which means more decisions, more doubt, and no additional coverage. The right answer for him runs the other way: fewer clubs, wider spacing, and the freed slots spent somewhere the spread is naturally narrower, which is almost always the scoring end.

A wide pattern is not a reason for more clubs. It is a reason for fewer, spaced further apart.

Why nobody arrives expecting this

Because every piece of fitting content and every screen in every shop leads with an average. Averages are comfortable, they compare well against a friend's number, and they map onto the way golfers talk about distance in a car park.

They also throw away the single most useful thing in the data. An average tells you where the middle of the pattern sits. It says nothing about how wide the pattern is, and width is what determines whether a club selection decision is real or imaginary.

How we read the sample

Eighteen recorded swings. Remove the two longest and the two shortest — a symmetrical rule, so it cannot be used to flatter anybody — and read what is left. The median is the middle of the remaining fourteen. The spread is the distance between the shortest and the longest of them.

We do not remove a swing because it felt bad. That is where fittings quietly go wrong. If a golfer hits one out of the heel every six swings, that is not noise, it is a feature of the sample, and a head that preserves ball speed on that strike is worth more to them over a season than a head that is two miles an hour faster dead centre.

Why eighteen and not eight

Small samples reward whatever you happened to hit well that day. At eight swings the spread figure is unstable enough to be misleading, and it usually reads narrower than reality because you have not yet made your bad swing. Eighteen is roughly where the number stops moving much, and it is short enough that fatigue has not set in.

Spread is a variable you can change

The part golfers find encouraging: this is not a fixed property of a person. Half of Golfer B's twenty-seven yards was strike location, and strike location responded to two things we changed the same afternoon.

  • Half an inch of length came off the club, which moved the strike pattern noticeably toward the centre.
  • A heavier shaft slowed his transition slightly and tightened the low-point variation.

He finished at nineteen yards of spread with a carry median almost unchanged. Nineteen is still wide, but it is wide enough to work with, and his set went out at thirteen-yard gaps with one long club removed entirely.

What to do with your own number

If you have a spec sheet from anywhere, look for the spread. If it only reports an average, that sheet answered a less useful question than the one you paid for. If you have never had a session, the quick home version is to hit ten mid-irons to a green you know the yardage of and note how many club lengths separate the shortest from the longest. It will be wider than you think and that is not a character flaw — it is the actual constraint your set makeup should be designed around.

See the Width of Your Own Pattern

It is on the screen within twenty minutes of you walking in, and it usually changes the plan for the rest of the session.