Don't know if they're deliberately doing this, but road people have been known to skimp on maintenance because by capitalizing it (letting things break down to where reconstruction is needed) you can use a different pot of money (usually federal and/or state for roads, which can stretch local dollars). In terms of actual cash, it makes more sense to maintain things so you can get all the service life that's feasible; but if your viewpoint is skewed by where the money comes from you might do something else. In BNSF's case, is some of the "capital investment" actually fixing down to the ground sections of track that have been left alone too long, hence now covered by the capital budget not operations/maintenance, rather than actually getting new capacity?