With enough back to back testing (offline map with bots), it became apparent that something else has a greater effect on mouse movement then the ferrites on my setup.
I found the post that started this for me:
I come to similar findings now. The ferrites and moving cables/fan wires around have an effect that can be felt through the mouse but electricity/EMI/RFI issues are not really something that can be measured or tweaked away so easily.I have messed around with ferrites and toroids and while they do make a difference for some (temporary) amount of time, they ultimately do not fix it. So that being said, I know its EMI affecting data cables in particular, likely power cables as well (I have placed toroids on the power cables and it changes mouse tracking drastically), I just do not know how to find out what is generating such powerful EMI in my electrical system. ~nuggify
I will not even talk about windows and bios settings, this does not reduce the input lag in any way. ~Ekwalipt
Need perfect electricity without electromagnetic interference. ~Ekwalipt
I am starting to understand, although at first, chasing the perfect mouse movement through tweaking and applying all sorts of settings seems so promising that it will yield fruit, but it never has consistency/permanence for some because of deeper underlying electrical issues.In ideal environment (good electricity, low EMI) even with unstable polling rate you could still have better input-lag and/or mouse movement than somebody with very stable polling rate but bad environment. ~ffs_
I also now understand why the Chief and others are so adamant in testing procedures and scientific methods. Placebo is real and pinpointing cause and effect is not so simple.
Now motivated to try out this overkill line conditioner(Topaz Line) I have along with grounding/earthing testing. I never bothered with the conditioner because it weighs like 50kg and I think it will consume more watts plugged in then the actual computer. Will update with findings soon.
TLDR; Ferrite beads/cores most likely do not do anything useful as a permanent fix for those with mouse movement/input lag issues.