Chill out dude.
Simple fact that that there are so many variables involved that there is no single answer.
Soil/hydro types (cec, infiltration, percolation and drainage rates), pH, fertilisers (I could write a whole page on this. From Simple things like Nitrogen being far more mobile to most other macro nutes to different types of Nitroge (No3/No4 etc dependant upon oxygen atoms and the effect on cation/anion exchange)
VPD, Co2 levels, Plant variety, curing/drying times or methods of trimming/temps/humidity levels are all other variables.
A simple example is I grow my own tobacco and we have to run phosphates down long before cropping or it causes poor burning.
I have also managed many sports venues turf surfaces and, although slighly off-subject, the principles of nutrient requirement for summer sports are the same. The year consists of late spring slowly upping N into bid summer then slowly switching we shut down in mid-late summer before a strip and re-seed in autumn with a very light p/k app. We don't run ferts late because of problems with disease caused by too lush vegitation.
Another method we use is both plant tissue and soil nute content (along with a particle size analysis and obviously pH). It's interesting to watch the interactions. Often not as you would expect. The more we look, the more we realise how much more we need to look.
Anyhow, rambling now but my point is that each growers situation is subject to too many variables to have one answer. I could probably flush my Hydroton tray of nutes in 1/50th of the time as someone in a clay/humus mix.
You won't find published dissertations or theses on the merits of flushing weed as, to the best of my knowledge, there are no educational establishments currently running Higher Education courses in weed growing.