A surprise: D316 (at the shorter dev-time) is delivering finer grain than XTOL in the shadow- and midtone-portions of the curve where it matches XTOL's curve. In fact, even the overdeveloped D316 roll matches XTOL's grain (judged by 22x loupes). The curve's shape looks like Tri-X. Here are the two TMX/D316 curves with the Tri-X/XTOL curve (in red) for comparison:
t.jpg
I think I'll boost dev-time of the green curve a little (to 14.5 min) to match the curve of Tri-X, and say, "If it's good enough for Kodak, it's good enough for me."And grain should still be finer.
PE: I appreciate all the help you provide. Thanks!
Mark

And grain should still be finer.
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