Seems to work in February as well. However, I don't really know how to avoid going through SEA when using kayak. Some go through MSP on the way back, some go through SLC and SEA on the way to ANC.
When I enter the whole string LAX-MSP-ANC-MSP-LAX in kayak the prices go up. I get the best price when entering LAX-ANC, but then I often don't get them to go through MSP.