That's a short-circuit (which I occasionally do) by taking the usual outcome without stepping through how to get there...
Originally Posted by Stephen Benskin
Steps for testing for Zone System film speed are well (and inconsistently) documented... There isn't any intention to include a safety factor. Its a specification of quality that shadow detail is required.
And it may not correlate to the first excellent print criterion, the negative that fits Grade 2 under Zone System, may well be exposed a stop above the "first excellent" print.