I can easily think of one aspect that might not be accounted for in this model (don't know if it is). Because of the effects of turbulence on terrain, winds are almost always faster as you gain height from the surface; in other words advective drag on the wind slows it down at or near surface levels. Elevation adjustments are "massive" in 22lr starting around 200 yds--it's sort of like lobbing an artillery shell compared to a faster centerfire cartridge. Thus, I think it's quite likely the bullet's trajectory will pass through a "layered cake" of different headwind velocities when shooting at longer distances. Food for thought
2.2 MOA might not sound like much--but you're talking around 10" at 400 yds; and that's assuming the trajectory is otherwise identical shot to shot. If any other factor induces let's say another MOA or 2 of variation that can mean missing the target altogether.