That could work, but Life Orb would be better in my opinion, Focus Sash effects get eliminated after SR, Spikes, Toxic Spikes, etc damage, so I would have to run a Rapid Spinner (too much support).
I actually considered that since it is one of the top 10 most annoying Pokémon. Encore / Toxic / Rest / Knock Off is so damn annoying. >.< Just think of having a sandstorm going (gives Shuckle a 1.5 SpD boost), and dual screens up. 8D