I don't think the big lines coming out of Canada running through the area around the Bakken run at full capacity anymore. Our Natural Gas imports from Canada have fallen a bit without any real loss in pipeline capacity.
For that data:
U.S. Natural Gas Pipeline Imports From Canada
http://www.eia.gov/dnav/ng/hist/n9102cn2m.htm
I agree I’m just saying it takes time to catch up.