You can clone two of the same type of input device by using the following undocumented method:

1. Factory reset the remotes (press pair 4x within 5 sec).
2. Pair one remote to a bulb (this may not be necessary, but I did this)
3. Hold the remotes next to each other, press both pair buttons for 10 sec. LEDs on the front come on, then flicker off.
4. Observe both remotes control the 1st bulb.

You can add additional lights with the following additional steps:

1. Pair one remote to a 2nd bulb.
2. Observe both remotes control both bulbs.