Be aware that seated skids can be pulled off if you have the strength and/ or low gearing but your are leaving more weight on the back wich will ruin your tire a lot faster than doing an out of seat skid.

Or if you have a front brake slam that thing on and lock your wheel, while seated. You can let off the brake off and keep the skid going pretty easily. The front front brake unweights the back allowing you to do this