Following Bill's suggestion, I have added a Development Time/CI plot. It highlights, with horizontal lines, the CIs I would presently associate with different N-times. If your CI-N relationship is different, and if you use my R code, you can just pass those as a parameter, it is explained in the comments in the file.
Delta 100 4x5 DDX 1+4 Dev Time-CI-N.png
As for real darkroom stuff, I have just run another test, at 4 min in DDX 1+4, to get the lowest contrast curve, which I was missing earlier. This is what my Delta 100 seems to be doing, I wonder how different it may be from others on the forum (I've only seen Michael 1974's plots):
Delta 100 4x5 DDX 1+4 4-24 min.png