Since reading about split-grade printing it has helped me a lot. If it's an average shot and exposed as normal, it generally will print to grade 2 just dandy. But not all of them are, so using split-grade printing to figure out the contrast is very useful. I usually start with 00 just long enough to put tone in the lightest parts of the image, and then use 5 to bring the blacks down where I want them (not that I'm racist). Sometimes an image needs dodging or burning and I'm not sure which phase I should do it in. A typical situation is burning in a sky with delicate cloud texture. I have been burning in with grade 5 but I think I might be doing it wrong, and haven't been happy with the results. Another situation I've run into is pictures of people that are harshly lit, so that one side of their face is dark and the other side light. I need to dodge the dark side of their face and then possibly burn in the lighted side, but I'm not sure which I should do during the high- and low-contrast exposures.