"increased spiritbond gain"

does it work ?

if i get idea right this stat increase spiritbond gain for every item equiped

so, i've tested how much my ring with "increased spiritbond gain +3" would improve,
i did wanderer palace in exactly the same manner (without dying, killing the same mobs) with brand new accesories once, and the other time with another set of brand new accesories and ring for spirit bond gain, the rest of items where already full spirit bond and didn't changed, and well... both times i got the same % spirit bond. accesories were ofcourse the same kind of item(even crafted by myself)
unless my spiritbond gain was improved by less than 4% this doesn't work for me.

can someone else test it ? or maybe i get the idea wrong ? it's hard to find detailed info about this mechanic

Assuming it's the same as 1.0, every +1 spiritbond is a mere +1% spiritbond rate.