but that doesn't address the problem
of rangers getting easy DPR. Even with two battle axes, he's probably still doing way more than the rogue, who doesn't have the wherewithal to achieve CA and get his striker damage. Also, do you disallow Iron Armbands? How about frost cheese? Even without those options, I bet a well-played or well-built ranger still kicks butt in the DPR department, given the circumstances.
You could also tell him that favoring axes requires him to wear heavy armor. Does he have masterwork scale? There are ways to up the effectiveness of tactics. Only reward XP for good tactics. Have a training session to go up levels where the rogue, in order to pass, needs to achieve CA every round of the training in some way or another, and avoid getting hit. Sort of like a skill challenge. Once the rogue's DPR goes up because he learned how to play the game, you might want to revisit the war axe nerf, because +1 dpr over battle axes really won't do much. The extra feat can and should be spent in that case to increase his DPR in some other way, such as Lethal Hunter, Prime Punisher, or any of the other myriad ways to do it.
Ahhh, the fun of playing in a group with unoptimized/poorly played characters pointing fingers at each other, eh? hehe. I don't envy you, as a DM.