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Yes, the bridge and bridge plate do work as a system. My objective is to design the system to spread load from the bridge as efficiently as I can, without causing stress concentrations, so minimising the material that has to be used, and hence the overall mass. So, for example, the front and back edges are curved to help reduce the "hardness" of the bridge edges. The bridge is also a cross grain brace, so has to be designed with that consideration in mind, too. So I use carbon fibre in the bridge and bridge plate when I want extra stiffness (not usually required on X-braced guitars). The traditional thinking on X-braced guitars is to run the bridge plate grain perpendicular to the top plate grain. I struggle to see the sense in that as it provides little extra stiffness in the long grain direction, which is where you want it on that design (never mind issues like bridges splitting along the perforations). So I typically set the grain of the bridge plate obliquely.

Bridges/bridge plates for falcate bracing follow the same design philosophy, but the execution is different. My bridge plate/cf assembly comes in at 10-11 grams. The six holes I drill in it helps reduce the mass.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I was a master class yesterday featuring Steve Klein. Someone asked him if there was a mechanical or structural reason for the shapes of his bridges, or if they were just for looks. His basic answer was that there is more mass on the bass side of his bridge to aid in bass sustain, and that the less mass on the treble side brought out more crisp highs. It definitely made me want to think a bit more about my bridge design, and what the end result of mass or lack thereof will bring.

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Jason McGowan
M&S Guitars
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United States of America, looks like another silent night
As we're sung to sleep by philosophies that save the trees and kill the children....
Casting Crowns

The issue with thinking of the bridge as having 'bass' and treble' sides is that a good bridge has to be pretty nearly rigid to work well. If it's rigid, it all moves as a unit, and 'bass' and 'treble' sides don't matter so much. Klien was an early follower of Kasha, who advocated a split bridge, in part to help isolate the bass and treble sides, and if he's still doing that, it could work that way, sort of.

Tapering the bridge across its width could have other effects, if you taper it enough, but that's a different thing, I think..

He did actually mention that he at one time was using Kasha's split bridge design, but I don't believe that's the case anymore. His bridge is very interesting to say the least. His website says that is is impedance matching.. Here is what it looks like:

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Jason McGowan
M&S Guitars
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United States of America, looks like another silent night
As we're sung to sleep by philosophies that save the trees and kill the children....
Casting Crowns

That sure looks like a Kasha bridge to me.

Thats kinda eclectic... Some bridges like the Breedlove appears to be just for show... and I'm not crazy about it. Taylor bridges look heavier to me than Martins... [just commentary...]

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com