I have two-way speakers with two inputs. Single wire was good. Doubling the run was a lot better. Keeping the double run connected to one set of output terminals at the amp end, removing the metal jumper clip at the speaker end terminals and connecting a cable to each individual terminal sounded best. This has been true with all three monitor speakers I've used - Sonus Faber, Silverline, and B&W. If you can't split the runs at least make up a speaker wire jumper to replace that metal clip between the bi-wiring posts.
Biwiring: can you really hear the difference?
What are people's experience with biwiring, and do you really think it makes a difference over just getting a jumper?