I had been following this 7 (or 8?) point white-tailed buck for over an hour when it bedded down. The deer became more and more tolerant of my presence and I was able to work in close enough to get a clear shot.
While my preference is for the look that longer focal length lenses give me for wildlife photos, I would not have been able to get a clear shot with these longer lenses. There was simply too much brush for use of the longer lenses here. That the 200-400 L offered me best-available image quality in a range of focal lengths was very important on this trip.