Bet they could built the Keystone pipeline in less then seven years!
The problem is the market is so volitile... that on a day by day basis capital ivestment decisions change based on the WTI/Brent Light Sweet Crude spread. Rail is there already and transload sites require very little (comparitive to a 1500 mile pipeline) infrastructure to have up and running in as little as 3 weeks... 1 week with an existing, underutilized siding.
Many oilmen want immediate NOW NOW NOW ways to play the spread... they are not waiting for piplines.