Ann: OHD Project Update, page-160

Fooca, I think one of the points John Wick was trying to make was that these trials are trials. They make the fertilizer, but then they are not sure what rates to apply. For example they might try 3 mm per litre on tomatoes and get some sort of result. Then they may try heavier rates and see if there is any improvement or not. Too much fertilizer might burn the leaves or roots. So then they might try 2 mm per litre.
Then they might try the same for wheat, barley or whatever, but it probably wouldn't be the same for everything, hence the need for trials - and this probably explains why they decided to trial the factor of 4 brew, whatever that meant. They were probably hoping for some sort of surprise results that may have appeased shareholders for the balls up.
While we are on it, there would then be other things to consider - eg weather, climate, optimum time in plants growth cycle to apply etc etc.
Think it would be quicker to find some lithium