I don't do my own wheels, but from what I've read, spoke compound is an important part of the wheel build, too. It lubes the threads when you're building the wheel, which helps prevent too much spoke-twisting, and then when it hardens it acts like threadlock. Also, it's important to load the wheel to let any wound-up spokes unwind before final truing. IOW, there's more to it than just turning a few screws.