I'm going to pour a little more on this thread
What does shooting 10 shot groups prove? And what does that have to do with hunting, or practical accuracy for that matter?
If a fellow hits what he intends with his shot, isn't that the definition of "good shot"? How does it matter whether he's shooting a 30-06 or a .223 if he hits what he intends? Old timers defined a marksman as someone who could shoot up to the limits of his weapon.
I reload 223 for $.26 each, 45-70 for $.70 each. I can buy new 223 for $.60 each, and 45-70 for >$2 each. Even the 30-06 is $1.60 a round if you don't reload. So the 223 is much easier on the wallet - cheaper to put in the rounds to "learn to shoot".
Now if the object of the shooting exercise is to put 10 shots in a tiny group, my 45-70 will put more wear and tear on my body than will my 223. But truthfully, my Guide gun groups as good or better than my AR.
If you're going to hunt with a 7lb pack rifle chambered in 300 Win, and you don't reload or have access to a shooting space except the annual "sight-in days" - you're not likely to be happy with your hunting shots. Shooting proficiency is like golf - you've got to do it to get good.
To say "everybody shoots a lighter recoiling weapon more accurately" is not correct. Cheaper - yes, less fatigue over long sessions - yes, but more accurately - nope.
Just my opinions of course.