Above is an image showing what i'm on about...
40mm kill on left, showing a 4.5mm pellet, leaving 35.5 before you split. Assuming a 12.5mm edge to edge group at 50 yds in the the middle image.
On the right is the effect of wind pushing that over, and if you allow the right amount of wind, and are on the level, no problem.
If however you allow the same amount of wind, but increase the dialing error due to rangefinding or not being precise with your clicks, or for whatever reason not dialing the right amount, on a 50 yd target you can see the effect of wind on the group... being 4 clicks out the red area shows you have an estimated 45% chance of hitting it. What 1/8 clicks allow is to get in between
these 2-3-4/4 MOA jumps and just giving you more possibility of hitting. It's a smidge, granted, but it's of no harm and of a smidge of benefit.
This is why on windless days you can be way out and still get in the kill. But with wind it becomes much more important to be spot on with the dialing so you can maximise your chances of getting in the kill.
If you use the tactic on slight wind days of letting it drift by just giving edge, then you need to be just as spot on, because a couple of clicks out will see you coming up and out even if the shot doesn't move left or right (and thats assuming you've allowed for your group size to start with. Holding edge and seeing a pellet move in an unexpected direction could be as much your grouping ability as it is wind... but having clicks that jump further distances like 1/4 MOA will only have you futher away than you should be (all other things being equal) unless you are spot on to start with.