Because nothing surprises us anymore, the reality of two brothers squaring off in the Super Bowl already has been trampled on by some as a tired narrative.
Cynics aside, Jim and John Harbaugh meeting on the NFL's biggest stage, if nothing else, remains a numerical rarity.
Kathy Ensor, a statistics professor and department chair at Rice University, placed the odds of this happening at 1 in 255.
One in 255 doesn't sound that outrageous, but if you widen the pool to 150 coaches -- accounting for coordinators, ex-coaches and Bowl Championship Series coaches with the potential to reach the pro head-coaching level -- the odds jump to 1 in 11,175.
And when you factor in coaches from every level, Ensor described the chances as "astronomical."
We like football. We don't like math. We'll take her word for it.