That would be the procedure for a 'problem' car. Normally a cooling system is self purging so you wouldn't have to go through all of that. You'd just add coolant as needed. If for some reason your particular engine is overheating, then Yah, the above procedure should be followed to eliminate the variable of trapped air in the system.
Keep in mind as well that the 'gasket leak repair' that you added could clog some of the tubes inside your radiator if you already had a corrosion build up. That's why I said that you should probably have your radiator flushed (to eliminate that variable). A garden hose flushing will probably not help in this situation.