Well then there's no availability, it is certainly the most deep-discounted eco fare out there, both for domestic and international travel.
But, instead of just quoting SOME part, do the whole (from flyerguide): "Seasonal Economy Promotional Fares/Reduced Fare Gov’t contract etc"

Government, industry and agency discounts are commonly something like ID, AD or so.

Thing with united domestic is that most ow/rt trips book into something like T or so. But I have two itineraries on screen right now with UA, one booked completely in K for TATL travel via east coast to the west coast and one solely west to east in K and L.

Sure they are going to ask for an ID... but this ID is going to be a government issued passport or DL for domestic legs in the US.