Some of the pictures were pretty tricky, I think identifying one that you had glassed in the field would be easier. The shoulder hump is pretty tell tale and some of the pictures did not have a shoulder shot.
This is all theortical for me though never hunted in a region that has both species.
It's all theoretical for me too - I've never positively seen a grizzly. I might have seen one once when I lived in Banff, but I'm not sure. There was some decent Black Bear hunting around home, but I was never successful, and I refused to "get in line" at the dump for a shot at a garbage bear.
Jim Zumbo, Craig Boddington, Ron Spomer and Wayne Van Zwoll are all solid contributers to the modern hunting literature. Through their gifts (both hunting and writing) they make us better hunters. Whether it is letting us learn from their mistakes or by teaching us new techniques,they help us harvest more game. But I suggest looking to the oldies, the fathers of the outdoor writing craft, to learn tricks that you might have not used.
I chose to shoot the 270 winchester because I grew up...