I have a clear dark glass façade on an insulated redstone conduit with a lever on top. If the lever is on, the conduit connector becomes invisible in the façade, unless you are holding the yeta wrench, but when the lever is off, the connector is rendered.
https://postimg.org/image/5lu2zhj61/ - Lever Off - Conduit Rendered
https://postimg.org/image/nsjtvr25r/ - Lever On - Conduit Invisible
https://postimg.org/image/45lz0t1c9/ - Lever On w/ Yeta - Conduit Rendered Again