you add weight until you feel a small deterioration in performance it just means you're running too much weight the vario shifts gears too soon the engine can't get into the powerband, the trick to vario tuning is to make the transmission stay inside the powerband of the engine.
if i feel i'm close to the ideal roller set-up i just incrementally add or subtract weight 1 roller at a time, not 3, not 6 but just 1 roller, this may sound contradictory & strange to you all but it works for me.
my set-up uses tandem rollers meaning 2 rollers of the same weight are positioned directly opposite to each other to achieve balance so when i need to change the weight a very small amount say .5g or .3g i just take out 1 roller instead of 3 or 6 rollers like what you normally do (i was doing the same thing you did 5 years ago).
for example i have 2 x 5.1g, 2 x 3.7g & 2 x 2.7g, if i just wanted to add .3g to the total roller weight i just change one 2.7g roller to a 3.0g roller. do you get me on this one?
you'll hear a lot flak on this type of approach b'coz they are not used to this but people fear what they do not understand, tuning will not evolve if they played it safe all the time & if that were the case we'd still be stuck with straight tubed exhaust pipes instead of the cutting edge chamber pipes we take for granted.