UP may in fact be cash poor, though it's hard to tell, but I see this more as positioning for STB arguments. If CP in fact scores NS, that leaves only CSX in the East and two big 'uns in the West. Only one of the Big Westerners can have CSX. UP wouldn't want BNSF taking CSX with a pile of Warren's cash, leaving UP to argue with KCS and CN over the tailings. So better to take a no-mergers-by-anybody position and hope that by the time it gets to STB things won't have changed too much in its makeup and viewpoint.