IMHO, the issue isn't whether a 7mmRemMag is or isn't a "proper" deer rifle; rather, why is this fellow having trouble?

I've got a couple 10 gauges (a Ithaca Mag 10, and a "no name" Spanish SxS double) and while their recoil is "different" from the sharper jab of a NA big game rifle; it still serves as abenchmark of ones "mettle for recoil" and one that should serve as a sufficient"stamp of approval" for handling a 7mmRemMag. This leads me back to the brass tacks of "recoil managment" namely that I thinksome of the "tacks" must be missing.

If a guy can handle 3.5" 10 gauges no problem, then under proper conditions a 7mmRemMag should be NO problem at all either.
So the actual recoil of the rifle is not the problem, it is managing that recoil with a scoped rifle set up thatappears to bethe problem.
One can sellthe rifleand simply move away from 7mmRemMag; however, IMHO the "high power rifle shooting" problem will likely follow.

I wish I could have just one night (to work over the rifle - length, relief, weight, etc.) and a dayof shooting (technique, simulation, rules, mixed fire, and practice) with this fellow to show him what I mean. Dollars to donuts it would be 75% fixed in that time, the balance would come off in time as long as the fundamentals were not abandoned.