Its clear that the current style of testing isn’t going well given these test have gone on for months with little to no impact of the games dreadful peak time performance and as much as anyone could ever love a balance change of removing proc sets, I do not think that they are the be all and end off to fix lag (as much as I could possibly hope they were). I think a better approach to trying to fix the current problem would be to start from the ground up and strip Cyrodil to an absolute barebones , rock bottom state and work back up from there.
Start a weeks testing with nothing other than solo players in purely stat based gear, with no pets, no CP, no procs, no siege, not even any guards. as simple as the game could possibly be. Then each week add back 1 aspect, like CP the next week, small groups the week after and so on. I feel like this will help isolate what it is that causes the major lag issues far more precisely than cherry-picking random aspects that may or may not make a noteworthy change. This would cause possibly a few months of sub par gameplay for some, however finding and resolving the game’s performance problems seems a more than worthy cause to endure it for.