Yes it would... Is that something new in D/P? I can add that in there fairly easily. Though, I still need to add in the code for the new abilities, yet...
Yes, the Rock-Type SpDef boost is new to D/P.
Just to note, it's applied directly to the stat, not counted as a stage.
Example:
Instead of Iron Defense+Sandstorm equaling 3 stages (250% of original stat) it equals 2 stages and a 1.5x multiplier (300% of the original stat). Seems like common sense, but I just figured I should make sure you knew.
Also, I don't think it's been definitively tested... Does it actually boost the defense stat, or simply reduce the damage after other calculations? The difference it makes is minimal, but X-Act and Peterko should test it if they haven't.