...makes things happen quicker and cheaper.

I found a preprint of the article (from July 12, 2012) here. Haven't had a chance to read it through yet, but the authors' Discussion and Conclusions provides a little more clarity than the popular article:

I would expect most modularity in evolutionary biology to stem from modularity in the gene regulatory networks that control organism development. So understanding how modularity in these networks is cheaper would be crucial.

Anyway, it's a really interesting result. I'll likely try and find a way to use it next time I'm doing evolutionary computing

Paper:
http://rspb.royalsocietypublishing.org/content/280/1755/20122863.full.pdf+html

Data and src:
http://dx.doi.org/10.5061/dryad.9tb07

animated video:
http://dx.doi.org/10.5061/dryad.9tb07

As any competent programmer knows, modular code is much easier and faster to debug and correct.

The benefit is in reduced time and effort to develop a system that "works". It may not be the "best" system. However, aiming for a system that at least "works" is why there is so much variety in the universe.

Even as a metaphor, the term "cost" is misleading.

If the universe were designed on the basis of a least cost model (think cheaply made imported junk from low wage countries), our world would have disintegrated a billion years ago.

Cost can really be any function of a structure. amount of materials, time, pain (e.g. SW that is easier and fast to debug costs less time and pain), etc.

"wiring cost" in their case refers to things like total length of the network graph. Or the energetic or raw material resources that an organism needs to grow and maintain itself.

Whether "fixing" a mechanical or electronic device (or getting a prototype to work), "divide and conquer strategies" work best.

Most systems are over-designed, over-engineered and overcomplicated. The worst software code is referred to as spaghetti code for a reason.

The key to understanding a system is to first not describe it in terms as muddled as economics terminology, which is misunderstood by most people including a lot of posters on DU.

From the article linked to in the OP:

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For years, the prevailing assumption was simply that modules evolved because entities that were modular could respond to change more quickly, and therefore had an adaptive advantage over their non-modular competitors. But that may not be enough to explain the origin of the phenomena.
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They should have stopped here.


However, they had to add:

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The team discovered that evolution produces modules not because they produce more adaptable designs, but because modular designs have fewer and shorter network connections, which are costly to build and maintain. As it turned out, it was enough to include a "cost of wiring" to make evolution favor modular architectures
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They assumed that their model mimicked nature, which doesn't follow. The only thing their adding a "cost of wiring" proved is that THEIR MODEL required such an addition, NOT that "nature" required it.

"we tried for a Beagle but got a Hyena instead...oops".