Pomeroy and Nate Silver have weighed in on both of these matters to change my view.

Also, offenses are in fact more consistent than defenses at home and the road. While both play better at home, defense does more so. A couple of links among many:

http://fivethirtyeight.com/features/live-by-the-three-die-by-the-three-is-mostly-a-myth/

http://beforeitsnews.com/sports/2014/02/defense-travels-2554650.html

"The obvious, and rather disappointing, conclusion is that the hypothesis is bunk. The defensive teams actually perform ever so slightly better at home vs. on the road than the offensive teams do – "

There is no data that suggests that 3 point shooting teams are less consistent over time than those which which rely less on the 3.

FWIW