@Haejin, Great video and thanks! The mute button is very helpful indeed:) Learned much about the leading diagonal and where that can break the rule of 4. Every one of your videos builds upon the others and the information is there for those with eyes to see and ears to hear. I have personally watched the Fib tutorial 4 times and still have questions, so my intent is to watch it 4 more times at least! Many thanks, and much respect from a longtime follower.