I have been playing offline, and have started the perilous grind for covenant offerings. I read on here (see revision 38, it has since been removed and I can't link to it directly) that changing one's equipment periodically may help improve one's chances for obtaining items. I also saw some murmurings on other sites that this may be the case. I tried changing torso, glove, and leg armor out of desperation, and it might have worked.
I'm not sure if this was coincidence or not though. I'm also not sure if there is a specific thing I can do to reliably improve my chances (say, maybe changing my rings would be more effective, or maybe changing my headgear would be more helpful than just keeping the Symbol of Avarice on constantly).
Is there any definitive research?
Is this something consistent in other Souls games?
EDIT: I'm looking for ways to increase my odds of finding these items outside of increasing my Item Discovery stat. I may not have made that clear above.