I am with Peanut.
The City had to know that building to the south like mad would do this to Deerfoot. And convieniently the Province is responsibile for it so it gets all the flack. IMO its a classic Bronco tactic.
Also, if the commute is say 50 min and widening it 1 or 2 lanes would only decrease it by 20 minutes. Its not economically feasible IMO. And its a cost of living in that area.
You can also use the C Train if you dont like the Deerfoot