I am on the email list of Lou Stagner, the head of data for Arccos. Here is a clip from todays email. He looked at players who gained 10 yards or more and those who lost 10+.
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In order to qualify for this analysis, a golfer needed to play at least 25 18-hole rounds per year for two straight years.
For each "season", I calculated a players median distance for shots hit with driver. I was looking for players that gained at least 10 yards compared to the prior year, as well as players that lost at least 10 yards compared to the prior year.
For players that met this criteria, I looked at their average strokes gained per round for each year.
The Stats
Players that GAINED at least 10 yards with driver:
81% scoring improved
65% scoring improved by 1+ strokes per round
44% scoring improved by 2+ strokes per round
29% scoring improved by 3+ strokes per round
17% scoring improved by 4+ strokes per round
Players that LOST at least 10 yards with driver:
65%: scoring got worse
45%: scoring got worse by 1+ strokes per round
27%: scoring got worse by 2+ strokes per round
15%: scoring got worse by 3+ strokes per round
9%: scoring got worse by 4+ strokes per round