But what is life like for the tens of thousands who do? How does their "modal split," as Metro-North so elegantly terms the jigsaw pieces of the daily commute, fit in with their workday?
As Finn explained to me over e-mail, "Often after a race you will hear a Kenyan runner say something like, 'I felt good so I decided to push.' Rarely will they say, 'I was running 4 50-mile pace, so I knew I had to pick it up.' " And while some in the Kenyan contingent do track their splits and pace, Keitany does not.
The tabloids did their best to whoop the split into a scandal, but were defeated by the unusual dignity with which the three handled the drama, and even now that Sheen is part of another celebrity couple, dating the actor Rachel McAdams, he still barely registers on the radar of the celebrity media machine.
Furlong, who seemed to age several years in the opening days, sounded eternally grateful, but the athletes did their part, too, in these split-screen Olympics, which really should have been called the Vancouver-Whistler Olympics, just as they were early in the bidding process.
But until the boy band actually gather for that somber press conference (as boy bands do), discussion of their split must remain misty and speculative.
The decision to do so split their union, the International Association of Machinists and Aerospace Workers.
Seats where the Tories could do well on the back of economic growth, if Ukip and BNP don't split their vote: Birmingham Northfield Labour majority 2,782 20100).
Because the United States has no such system, members of Congress can (and often do) split with their party.
Runners stretch their hamstrings before hitting the pavement, gymnasts do hyper-splits during their warm-ups and yogis wind down their practice with some forward bends.
