You and the man who told you that are 100% correct. Any motor should get temperatures of the fluids within it close to the temperatures they are designed to work at before operation. For example it was 0 degrees this morning here and all fluids within the Jeep liberty had jelled....the oil/power steering/transmission fluid etc...let alone the need for the anti-freeze to heat in order to make the cab bearable....you are always better off warming any vehicle up.
Road & Track and Pop. Mechanics say differently...
http://www.roadandtrack.com/car-culture/videos/a30249/why-you-shouldnt-warm-up-your-car/
http://www.popularmechanics.com/cars/a19086/warming-up-your-car-in-the-cold-just-harms-engine/
if you’re using the correct viscosity oil, warmup is not necessary! And I’m just a girl!