This comment could be irrelevant, but I recently bought a Winchester 101 Supergrade (Made in japan) with double triggers.
The front one function like a non selective single trigger (first pull discharges under barrel, second pull the upper) and the rear trigger only discharges the upper barrel.
I do not know if the same factory in Japan produces both, Winchester 101 and Browning Citori.

Regards,

Jose M. Fernandez