Warming up the car

I see people are warming up their cars for long periods of time more and more these days. I'm trying to figure that out. I understand that people like to get ito a nice warm car in the morning when they leave, but there are laws about idling (usually the limit is five minutes) not to mention the waste of fuel.

So all that aside, let's discuss the two schools of thought on warming up the car:

Warm it up fully vs. Don't bother

I keep running into people who say you MUST fully warm up your car before driving off. Everything is at running temperatures. You're good to go. But I find that when you sit there idling, it takes a VERY long time for the car to warm up.

When it's cold out you should only start the car when necessary because that's the time that the engine's intermal components are at their most vulnerable. The oil turns into molasses in the part and it takes a while to send it throughout the engine.

In other words, you start up your cold car, it sits there idling high with poor lubrication for 10-20 minutes, you kick down the idle and after wasting all that gasoline you drive off.

Those who don't bother warming up just get in the car, start it up, kick down the idle, drive off, and within a couple blocks the car is already warmed up. So you use the car as it warms up, less wasted fuel. Plus when the car is moving, it usually runs at lower RPMs than a car sitting and idling and is easier on parts that require lubrication.

I don't have time to waste for my car to warm up on it's own. I know my car can take 30 minutes for it to warm up when it's sitting there idling. However, if I drive off it'll warm up in about half a mile.