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Skipping the big multi-quote response: Big business and a quick link between rooms in one building (range.. jeez.) are two totally different worlds.
I have worked more than one place where links inside the same facility (building, even) have been a challenge to the length limit for 1GE over multimode. 10G in that situation is just hopeless. We tore out all multimode cabling and replaced it with 9/125 all over, because it was so *bleeep*ing annoying to try to build short enough links. As I wrote upthread, one path might be possible, but if you want two, dispersed, to safeguard against sparkies with a cable cutter, or fire, one of them usually ends up on the scenic route.
Besides, that "quick link" usually ends up being a vital component in something 2 years down the line, so it pays to do it right from the start.
I bet you're fun at home - oh crap I moved the PC, time to get the microscope out..
My PC's are on either GE copper or wifi (laptops and mobiles/tablets). The switches in different parts of the house and garage are interconnected with single mode fibre, at either 1 or 10GE speeds. When I move one of those inter-switch links, yes, the scope comes out. The servers are on 1 or 10G copper (DAC cables, as they're in the same rack as the core switch) as needed.
This is applied engineering, fueled by hard won experience. Not religion or dogma. I'm simply trying to solve tomorrows problems today, by doing things right from the start. At work or at home.