Ok I think I understand it now. All this flexibility makes it confusing. It appears Garmin was really thinking about you having 2 switches even though it can be done with one. I'm going to have to think about this more. As the builder I get that you will know that the Wig-Wag switch could be on and the Landing Light switch would override it. As some other pilot maybe not. For me that tends to push me in the direction of using a single multi position switch so that it isn't quite as flexible but more intuitive when looking at the switches.
The other alternative that seems intuitive is to just use a single two position switch for the landing light (switching the light enables on) and enable the automatic speed sensing wig-wag function. The Wig-Wag then happens in the background and it really doesn't affect the pilot operation.
Michael, I actually have mine setup different than your drawing. I have one landing light on each light output. My Taxi lights are not connected to the GAD27.
I'll have to think about this more before finalizing my selection. The automatic Wig-Wag seems better in a way. Jeez too many options here.
PS: Garmin a simplified truth table might be helpful with the configurations included.