Color me stupid here, but don't the armed forces now train with blanks and "laser tag" gear strapped to their rifles? Never mind simulators like F.A.T.S. And if you confuse the ballistic curve of a .22 with a 5,56, 9mm, or .45, you aren't apt to to do well in other training scenarios either...
I believe one major reason I won so many matches at Ft. Benning was partly due to the mass quantities of .22rf rounds I sent downrange before the matches. Transitioning between calbers is probably beneficial, as the rimfire lets you run to the ragged edge of sight reaquistion. When forced to allow for the longer recovery time of the larger caliber, it feels like you have all the time in the world to get a good sight picture whilst riding the rifle down back onto the target.