0.10 in a 16 would be fine for all-season grouse/WC here in Maine. That is saying something.
Choke configuration does matter. One .010s may be better than another.
Regarding use of open/no/almost no chokes (whatever the heck MM meant by that) for everything, there may be a better way to guarantee you will never develop as a SC shooter...but right now I can't think of one. That was one of the most poorly considered pieces any shotgun writer ever put on paper. Using only open chokes is like betting against yourself, encourages such things as shooting twice at the close target, and provides fallacious input to the brain by way of misses on distant targets that were correctly pointed. You can groove and break a 40 yd target with a .005 12 ga often enough to convince yourself it can be done. But this is no way to develop in SC. Of course, to know this last part is true one would need to actually pattern at distance. I suspect MM did not pattern much, if at all.
I am 100% with Stan on this.
Sam
