As foxy2 clearly pointed out, there are many points for refinement; it's definitely a work in progress.
Over at the Shroomery there's been mention of starting off with a more potent species then adjusting the solution to meet it's needs by testing biomass yields in an array of cultures with different nutrient makeups. Higher biomass would be direct result of better glucose utilization and would most likely have higher alkaloid content. If these species can be efficiently culture in a liquid nutrient solution and present increased activity in the presence of raised glucose concentrations, the theoretical alkaloid yields could easily reach over 2% psilocybin.
I believe that would be the highest psilocybin content that I've ever seen reported. Roughly 4 times stronger then you're average Ps. C. culture. High volume mass production techniques could yield over 15 g of psilocybin... but it's only theory for now.
-Zen