Ten times the previous number of layers every pass- the powers of ten quickly get you to full mixing. Nine times through and your talking a billion layers.
I think some of these mixes would look much better than the final product if it was left in the mid way point. When all the colors are spread out but not mixed yet. Like at 1:02
You should wear gloves while working with dies. You are at high risk of getting bladder cancer. Trust me, I have it and just had my 2nd surgery removing tumors.
there are so many times the wild unmixed patterns coming up from underneath are so beautiful, they'd be fantastic phone backgrounds, or desktop wall papers, or big wall paper murals...