If your solution to this is to restrict "magical" powers to magic-using classes, we're back to the 3rd edition problem that non-mages can't have anything nice.
I played a swashbuckler/rogue who was attacking seven times in a round and could duck under a dragon's belly without fear. I'd call that "something nice".
Literature and cinema are full of examples of smart, cunning people inexplicably closing against a warrior. Is it really so bad to add it to the game, especially since it's a neat effect with a lot of cool tactical applications?
If it were slightly rewritten, it could work. How's this:
Attack Cha+2 vs. Will, Burst 3
Hit: You pull target two squares.
Secondary: Attack Str vs AC
Hit: 1[W]+Str
This makes the power very clearly a "taunt" which is more likely to affect dumb grunts. (I'd be tempted to add in that it doesn't work on anyone who has a Basic Ranged attack, but that might complicate it too much.) I upped the damage to compensate for the fact it's less effective.
You wouldn't have a problem with CAGI if it were a Divine or Arcane power.
That's right, I wouldn't. Just like I wouldn't have a problem if "Fireball" were an Arcane power. Because, uhm, Arcane and Martial powers should be *different*?
But you make my point for me, quite well. CAGI (among other powers) cannot be easily modeled or justified as something which occurs in a battle (and remember, it's an encounter power, so it will come up a lot) as a consequence of "skill and/or training". It's a 100% game effect. You use the power, you arrange the pieces, you resolve the effect, and you disconnect yourself from imagining the battle as something "really" happening, any more than you imagine the clash of swords in a game of chess.
Why stiff people just because they use the Martial power source?
Why bother having power sources, then, if you can do anything with one you can do with the other?
I'd actually like to do an all-martial campaign, which is why I've been studying the martial powers more than the others -- and thus, constantly stumbling on these head-exploding quirks that could have been eliminated with another round of editing or two. They fixed Stalwart Guard; I have hope for the future.