John C said he'll be reviewing that method on Monday. It could be a bug, that the % boosts are stacking incorrectly. Guess John will shed some light on the topic soon.
Wilson
said
:
Why do people think it is something to do with Morytania diary? I tried pickpocketing elves and gnomes and the fail-rate was really high.
It only works for NPCs in the Ardy area, I think the Ardy 2 + Ardy 3 effects are stacking as well.