This misleading article refuses to die. Here is why this is bad advice:
1. Both defroster and heater take time to start working. If you start driving right away you will get foggy windows and no hands-free way to clear until the car warms up.
2. Cold oil does not lubricate as well, it is bad idea to apply load (start driving) the car until fluids had a chance to flow. Synthetic oil, plug-in oil pan heaters, heated garage and so on help with this. Unless you have one of these, wait a minute or so before you start to drive.
3. For cars sitting outside you should scrape ice from windows and clear the snow. There is no reason not to start the car while you are doing this.