I have to say this is sounded like such a common sense idea at first, but in reality, the arenas that are the hardest for opposing players to play in are not really the biggest. They're just the areans with the worst acoustical designs (like the old Chicago Stadium, or Cowboys' arena in Stillwater, OK), and where there' a rich (I mean wild and rambunctious) basketball tradition. For football, where games are outdoors and acoustics aren't near a factor, I could see this, though even then stadium design and culture (or lack thereof) are influences. Why is it so hard to play against U of Arizona? Why is Arrowhead such a tough venue?
All that being said, I would agree that does take a critical mass of people to get a place rocking. But I think how close a team is to selling out is more a factor than the arena capacity. The Alamo Dome that's only half-full is not as intimidating as the local high school gym with packed bleachers.
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