They didn't recommend it just has it as an option, but if I were them I would do something other than that jumper plate, its a poor conductor . they are fine sounding speakers though, my third pair of sonus Fabers..
Bi-Wire Jumpers
Just an FYI I have a pair of Sonus Faber Olympica three's I am using Cardas golden reference, never bothered with the Bi-Wire option just listened for almost a year , then on a whim bought a pair of Cardas Bi-wire jumpers. What a difference ! those little plates were killing performance , those Jumpers cost me 100.00 and made just an awesome improvement in just about every aspect of the speakers performance, I was stunned. my advice, ditch those little metal plates as fast as you can. I think now I might just go for a set of Bi-Wire cables.