There are two distinctly different types of trackstand, too; and the easier one to learn is the harder to hold. When I was just starting out trackstanding, I would slow at intersections, climb out of the saddle, and wind up like a spring. I could balance for 10 or 15 seconds, and then take off like a rocket, but would fall if the light took too long. Then I learned the seated track stand, the true zen. Come to a stop, and release all built up tension in the legs. Just slowly correct for any forces pulling you to the ground. This is a true track stand, the other is just slow falling.