Yes it is, too bad Marcel left the hobby and isn't available to fill in the gaps or answer questions. Most of his experiments are incomplete, the writing is not polished, and a great deal of the site while plausible and logical, is still poorly cited unproven theory.
There is good information on the site(I especially liked the chemical analysis of different aquasoils) but you really have to dig, and ultimately most of it hasn't been reproduced or verified.
Many of the experiments are Ad Hoc and with changing too many variables at once so its difficult to draw any definitive conclusions.
Happi is one of the few promoting this material these days, its pretty obvious he would like better recognition for Marcel's work and methods. Unfortunately he didn't perform the experiments published on the site, and he doesn't seem to be able to answer detailed questions or to present the conclusions in a clear enough way that they can be readily applied.
'Marschner Ratios' taken from a dry mass elemental analysis and converted to dosing regime is quite a leap of faith, the assumptions made to arrive at the fert ratios and baseline concentrations are not explained well.