No, the space wolve scouts have another infiltrate-rule. Refer to Codex: Space Wolves for details.
And yes, it would be unbalancing, I guess, but still.
I always preferred the alternative Reserve-rule; you get half of your reserves turns 2, and hte rest on turn 3. The only thing yo roll for is to determine which unit is in which half. I am a tad sad that never made it into 4th ed.