Working on polishing/smoothing up the lock on my Traditions Kentucky rifle. It is a single trigger rifle but came with the tumbler used in the double/set trigger locks so I'm going to go ahead and add a bridle to give the tumbler more support and smooth out the hammer. The tumbler accepts a fly, is there any reason or advantage to adding a fly to a single trigger lock ? I have three single trigger lock rifles without a fly and have never had one hit the half cock on firing. -Thanks