I've been playing around with the timing of whipping our Granary, as well as whether to work an Unnetted Clam or a GH Mine on Turn 45.
We also have the same choice between an Unnetted Clam or a GH Mine on Turn 46, but we pretty much have to work a GH Mine on one of Turn 45 or Turn 46 if we want our Work Boat 3 (aka Work Boat Explorer #1) on Turn 47, so I am going under the assumption that we will work the GH Mine on Turn 46... therefore, it's not really a choice.
Some scenarios don't work out all that well, but the best scenarios work out as follows:
Scenario 1: Turn 45 = Unnetted Clam instead of the GH Mine + early Granary
Scenario 2: Turn 45 = GH Mine instead of the Unnetted Clam + early Granary
Scenario 3: Turn 45 = GH Mine instead of the Unnetted Clam + early Work Boat Explorer #2
On Turn 63, values have "stabilized" after two rounds of City growth post-Granary, so the results become equitably comparable.
As of Turn 63, here are the Food, Hammer, and Flask values, as well as the number of turns to Grow, the number of turns until our Work Boat #5 is completed, the number of turns until we learn Sailing, and finally, the turn on which Work Boat #4 (WB Explorer #2) is completed
Scenario 1: 29 F, 28 H, 130 Flasks, 3 turns to growth, 3 turns to WB#5, 7 turns to Sailing, WB#4 on Turn 58
Scenario 2: 28 F, 31 H, 128 Flasks, 3 turns to growth, 2 turns to WB#5, 7 turns to Sailing, WB#4 on Turn 58
Scenario 3: 27 F, 31 H, 128 Flasks, 3 turns to growth, 2 turns to WB#5, 7 turns to Sailing, WB#4 on Turn 56
For easier comparison, the Scenarios give us this much Food, Hammers, and Flasks over the lowest values out of each of those 3 Scenarios:
Scenario 1: 2 F, 0 H, 2 Flasks
Scenario 2: 1 F, 3 H, 0 Flasks
Scenario 3: 0 F, 3 H, 0 Flasks
Analyzing results:
Scenarios 1 and 2 are basically like trading 1 turn work of working an Unnetted Clam for 1 turn of working a GH Mine. Unfortunately, Scenario 3 "falls behind" by 1 Food that is simply permanently lost to us, due to the delayed arrival of our Granary.
Scenario 1, however, provides us with an awkward situation... on Turn 63, we are at our Happiness and Healthiness caps and have 12 more turns before the whipping Unhappiness goes away. The problem arises in that Work Boat 5 will be completed on the same turn that we grow into Unhappiness and Unhealthiness; the other two Scenarios will complete Work Boat 5 one turn before growth and thus we can start on our Settler without needing to grow into Unhappiness and Unhealthiness immediately. So, for Scenario 1, we would either delay building Work Boat 5 for several turns (completing it after Settler 3 and Galley 1) or else we'd complete Work Boat 5 immediately but then would lose some Food to Unhealthiness while building Settler 3.
On that basis, I would say that Scenario 2 is better than Scenario 1, since Sailing comes in on the same turn, while we have essentially only traded the values of one square (getting a GH Mine instead of an Unnetted Clam for 1 turn)... but that while building the Settler, Scenario 2 will pull ahead by a few Food that get converted into Hammers due to not losing said Food to Unhealthiness.
However, when you look at Scenario 3, it has the draw of giving us 2 extra turns of exploration with Work Boat Explorer #2 (Work Boat 4), getting it on Turn 56 as opposed to Turn 58. Note that I also had a couple of scenarios where I could get Work Boat Explorer #2 on Turn 57, but those scenarios were inferior in terms of total Food, Hammer, and Flask values.
Note that with the "LC1 #304" test run, the results of which are summarized in
Mitchum's latest table, used one of the Turn 58 options, but I'm not sure whether he used Scenario 1, Scenario 2, or even a slightly different approach... although by the looks of the fact that we got Work Boat #5 (Work Boat Explorer #3) on Turn 66 (i.e. 3 turns from Turn 63 instead of 2 turns from Turn 63 to complete Work Boat #5), I believe that he used Scenario 1.
As long as you agree that Scenario 2 looks better than Scenario 1, we only have to choose between Scenario 2 and Scenario 3.
So, in making that decision, we're looking at answering the following question: shall we permanently throw away 1 Food for 2 extra turns' worth of exploration with Work Boat Explorer #2 (and thus follow Scenario 3) by getting that Work Boat on Turn 56, or should we look at maximizing our empire's output by getting that extra Food and be happy with getting our second Work Boat Explorer on Turn 58 (and thus follow Scenario 2) as per the originally-planned arrival date for Work Boat Explorer #2?