You cant yank apart boards with those screws with a pry bar, at least not easily. More often that not, the boards will break before the screw lets loose.
You'd think they would remove easier than nails. Just unscrew them, but it dont always work that way. I just got done fighting with four 8ft. 2x6s that someone sandwiched together to form a post, and held together with 3 inch black drywall screws with phillips heads.
I got out my cordless drill with a phillips bit, only to find the heads were buried deep in the wood, and the wood had swelled around the heads. A few of them came out, but most didn't. Part of getting the head to grasp in the philllips bit is to determine the angle they were put in. Very difficult when the wood is swelled around the head. (The wood was swelled more than usual, because this was sitting outdoors for several months and the rain made it swell worse).
I spent nearly an hour and a lot of sweat getting the first of these four 2x6's apart, and almost every screw the head pulled thru the board, meaning I had to remove the whole screw from the next board with my screw gun, or a vice grips.
By this time I'm thinking that for the cost of an 8ft. 2x6, this is not worth the hassle. Fortunately the screws in the next layer were more visible, since the weather had not swelled the wood as badly around the heads. I was able to unscrew about 4 out of every 5. That's when I got a steel wedge (log splitting wedge) and drove it in right where the remaining screws were. Thus breaking the screws.
This worked much better and quicker. Although this is not something I'd want to do on boards that will be exposed, since the wedge left an indent in the board. But for framing lumber it's fine.
One of the biggest problems is the fact the screws were phillips. If they were the torx (star) head like they are using more now, they would come out much easier. I've always hated phillips for this type of screw. A bit rarely lasts more than 50 screws, and less for removing them. Yet, I've used the same torx bit for 2 years of hard use, and it still works.
The problem I describe above is even worse on decks. Due to constant weather, the screw heads often can not even be located, and if they are, the screws have rusted and the boards swelled, and even a plug in drill can not often remove the screws, or the bit will break.
I posted this to see if anyone has any other (maybe better) methods for removing these screws. Mostlty related to removing them from boards that were screwed together. Not the little ones actually used for drywall. Those little ones can generally be pulled out with a claw hammer, or just broken off.