Mortal Lamina question

this katana has 30% guard break
so, my question is that how guard break stat would add up with gears?
eg. i have mortal lamina with mardula, ghost zipper and dark talisman power.
so, will the guard break chance add up or will activate individually?
i have this thought because i noticed that when guard break activates it shows from which equip has the gb activated.

 

The maximum guard break/ anticipation chance won't exceed 30% so it's pointless to buy more guard break item/ xtals.

 

thanks, didn't knew this stat had such small cap

 

I noticed this too, sometime ago I had finstern and ghost zipper and all the time guard break proc'ed was with staff's symbol.