I tried dubcorks and found it pretty hard to get the second cork, I also started with kangs, which are easier in my opinion. I am getting the kangs, but I still have problems with either over or underrotationg the second flip.
Cant say anything about switch doubles.
Just get out there on a waterramp and try the trick you can visualisize.
I wouldnt recomend doing so on snow though
...skiing is a serios addiction, probably can be compared to crack...