Interesting. I think I did not catch this argument in the way Pope frames this (in his paper, 10 questions about LES) He talks about any parameter of interest, and how it is split between resolved and modelled. So I figured I may very well apply it to all of KE. But what you said brings to mind an argument I read about spectral solvers, where we can eliminate pressure from the equations... It might be analogous to filtering out the bulk/mean flow effects from analysis. Sad for me as my resolution index just dropped to around 0.6 🥲