Would the process work for flours of different particle size distributions? Yes. The sieving step of the process is designed to take care of this. Though fiber can be separated from flours of any size distribution, separation is more efficient at coarser sizes. If particle size of flour is very low, it would be better from a separation efficiency point of view to grind the flour coarser and use a second hammer milling step (after the separation process) to grind coarser fractions to match flour size to what it would have been originally.
Other fractionation processes also have been developed. What is it that makes this process economical and competitive? Other fractionation processes are inspired by the corn wet-milling process. The use of water in other processes makes them capital intensive (equipment needs to be bigger to accomodate the water volume) and energy intensive (need to pump water). Most of those processes are wet or at least incorporate a tempering step. Weighty Corn's process does not use water. Moreover, the protein content in fiber separated using other processes is 15% or higher, which causes problems in the pre-treatment step used in Gen 1.5 ethanol production. The protein content in fiber separated using Weighty Corn's process is less than 9%.