I'm using Celtic knotwork to practice parallel line, shading, consistent line, back cutting, sharp points, and polishing up metal. Work in progress, not "there" yet, but this certainly is helping me- esp. in awareness!
Good job, Cloudy! I'm really happy to hear when someone is concentrating on back cutting as it's so important. On designs like this it becomes even more critical. When left undone, the work looks unfinished and rushed. Celtic intertwining knotwork will place heavy demands on back cutting as there's tons of it to do, but the end result will be crisp and professional when time is taken to do it right.
Tira- I did both ways- roughed out the major outlines, not going all the way to the next edges at one time then went back and did each section one at a time, working very hard not to get over cuts.