My last statement was dubious, my apologies. I meant, as was my original purpose in making these calculations, that rot is, at its core, not enough of an influence except a small incentive to sell/buy food quicker when comparing islands having seasons to islands not having seasons.
Have you considered that having such a great amount of surplus while ignoring all production during winter and spring creates dubious numbers at best? If you do not produce enough surplus to cover the majority of your food needs in spring at 75% production, you will not produce enough to stockpile for winter and spring. Thus this is an impossible scenario. Even in this impossible scenario, it is only 20% that is lost due to rot, and in a similar scenario without seasons at least 12-18% of the food will be lost due to rot anyways.
I agree. Stockpiling great amounts of food will cause a sizeable portion to be lost due to rot. Keeping an extra 1000 bushels all year round on top of the X days' worth of buffer will of course produce a ridiculous amount of waste, losing ~10 bushels every day. That's fairly obvious. The formulae are available to all. The theory is sound. If the observations do not match the theory, it simply due to differences in assumptions.
As I have demonstrated, if all lords and margraves are willing to work together to simulate what I described, satisfying my assumptions, the result is clear. Rot does not play a key part in differentiating the food system on islands with season and islands without season. What does differentiate the two is the willingness to part with food as appropriate on the part of the lords and the ability to resist anxiety and gather surpluses as appropriate on the part of the margraves.
I maintain that when base production meets consumption, these formulae hold, and it is human behaviour that is different.