I'm pretty sure you are misunderstanding the mechanics of shields. Damage reduction is not the same as attack reduction. The damage source (attack power) sends a value (damage) to subtract from the opponent's health (damage dealt). If there is a shield like, say, Solar Buckler that reduces damage by 1, the damage sent is reduced, which also reduces damage dealt. Attack power remains constant.
If the card does exactly what it says it does, then I like it. Of course, all of a sudden a flying Nadir/Zenith deck is nice. Creature control combined with the ability to constantly buff your flying weapons is cool.