Why sloped hood on switchers?

Do I not remember correctly that the ‘yard’ vs. ‘road’ distinction is made for union-related compensation purposes?

I for one would like to see what was on the blue cards for those UP TR units bought in the early '50s to be road pushers. (The ones subsequently equipped with DB only so they could be operated downhill ‘light’ fast enough without wearing out their switcher-truck brakes…)

sw1 designer was on crack