Pretty much all correct....use an upward cant in the road, push forward a bit, then let the bike roll back. Your only talking about a couple of inches each way here... The biggest "trick" to learning how to do this is learning to do something that seem unnatural to cyclists, to come to a complete stop without putting your foot down, and then allowing yourself to roll backwards. Doing a trackstand on level/flat ground is slightly more difficult and takes skill....it's a neat skill to have, and people look at you from their cars while at stoplights...but it's also true that in that application, yeah...pretty much just a "ha ha...take a look at this!" skill.