The original formula calls for, IIRC, 35g of Potassium Carbonate. But even Crowley didn't know the exact composition of the carbonate he used. There are threads mentioning that the Kodalk version would be, thus, a safer developer, and Patrick Gainer computed the 35g of Potassium Carbonate to equal just over 112g of Kodalk. From that, I would assume the 100g here is more or less correct.
juan