Drip "Glide Switch" Design/Concept

So, I was looking through the Drip manual for the UE-100 EQ. I was curious about the Glide switch, which is suppose to take most of the pop out when engaging the eq. Obviously my interest was peaked on other uses for this, but am not clear on how to apply it to a design. Due to the fact that Drip doesn't add a ton of info on their circuit implementations. Here's just a screen shot of the parts and a little explanation.

He's using a 'crossfader' built from 2 LDRs combined with incandecent lamps. One lamp is on, the LDR's resistance goes down - the other is off and that LDR has a high resistance and vice versa. As he points out in the description it is relying on the slow attack / release times of the incandecent lamps. I guess he could also have used LEDs with a slower LDR or a little bit of an additional circuit to slow down the LEDs...

I believe this is often used in guitar amps for channel switching as a typical example.

Michael