GEEZ, Springer, you're not accounting for my share of the dekes yet! We should have have quite a spread this weekend between us. The fact is, your spread should be dictated by where yo9u are. If you are hunting private land, and/or based on strong scouting and knowledge of local patterns or where newer birds are feeding, you can really get by with few dekes, and I've ssen times over the years where numbers CAN work against you.
Now, public hunting may present an entirely different challenge, as you are competing for attention with every other hunter and their spread. I've seen larger spreads, diversity, gadgets (derned Mojos and crap!) be the differentiator here. I've always been a huge fan of a jerk line on windy days. I wouldn't trade that for an extra 2 dozen in my spread on a still day.
So to each his own. You can argue that there's some strategy based on this drivel, but typically, I have a hard to resisiting the primal urge to put as many decoys out as I can usually fit in a car/truck/SUV/boat/trailer, often strapping more on top, tucking full bodies in unused pockets of air in the back seat, you name it. I say bring what you can!