Wind deflection is a function of velocity loss, not time of flight. I don't think that the 200/100 group size ratio has much to do with wind.
An older paper:
WIND DRIFT AND WIND COMPENSATION
Shooters compensate for the wind by watching wind flags and holding off. If, for example, the wind flags show that there's more wind from the left than during previous shots, the shooter will aim slightly right of where he aimed during previous shots.
We assume that this compensation is effective; measurement of that effectiveness is difficult.
Perhaps, I thought, some measurement of wind compensation effectiveness by shooters is lurking in the data.
Group sizes at 200 yards are greater than 2 times 100-yard group sizes. For the 506 CBA National Match records from 2000-2013, 5 shot groups at 200 yards are 2.236 times the size of 5 shot groups at 100 yards. The ratio for 10 shot groups is 2.385.
"Wind", here, is whatever causes this. Wind drift is one of the causes; maybe light changes or bullet velocity variations are others. Note that with no Wind, 200-yard group sizes will be just twice 100-yard group sizes.
We expect shooters to shoot smaller groups; and smaller groups to indicate better shooters.
We expect better shooters to compensate for the wind more effectively. A shooter who compensates for the wind perfectly would shoot 200 yard groups just twice he size of 100-yard groups.
Then we expect group size and the ratio of 200/100-yard group size to be directly related. Smaller group shooters should have lower ratios.
I fully expected the slope of the chart of group size and ratio to be a measurement of the effectiveness of shooter compensation for wind.
Cast Bullet Association, (CBA), National Match data from 2000-2012; and IBS 2011 and 2012 Group National data was analyzed.
The only trend lines that I could find on any chart was using 5 shooter moving average data.
For CBA 5 PBB, HV, PRO and UNR and 10 PBB, HV and PRO matches there is no pattern on the charts.
For CBA 10 UNR there is a trend line upward.
For IBS 2011 HV, LV, SP and U matches; and IBS 2012 SP and U matches there is no pattern on the charts.
On the IBS 2012 HV chart there is a trend line upward.
On the IBS 2012 LV chart there is a trend line upward.
There's nothing I can find that's a convincing argument for a relationship between group size and the 200/100-yard group size ratio. The trend lines are few, and not very clear. If better shooters compensate for the wind more effectively, I can't prove it using the available data.
What does it mean, if anything?
I still believe that better shooters compensate for the wind more effectively.
I think that Wind does not have a very large effect on accuracy, and that there are other variables affecting accuracy that have greater effect and operate to mask the trend lines and confuse the analysis and analyst.
joe b.