Double clutching?

I've got question for all you out there that drive stick shift. How many of you double clutch (also known as double de-clutching)? I've been trying to learn and I'm not sure if i'm doing it right when I up shift. On the downshift, it's pretty easy to tell if your doing it right or not so I'm not too confused there. I'm currently upshifting regular or normal style and using the double de-clutching on the downshift (or european style). Any advice would be helpfull

double clutching isnt neccessary in a mazda 3. use for trucks or old cars.

This topic was just covered in another area, has a good write up...CLICK HERE