5 year old buck +
Let me be clear. My outer single strand is NOT connected to the energizer. It does not shock. It does not need to be in my experience. After one shock the deer will be leary of the whole setup and if they attempt to get in they’ll step over the first strand and try to go between the inner strands... and pow.
I actually found energizing all 3 wires on a Gallagher-style fence is important in my case. When deer don't get zapped by the outer wire, they just went under it. The fed on the beans between the inner and outer fences. Once between the fences, they then easily jumped the inner fence. Energizing the outer fence is also important because of the function it performs. It is tape rather than turbo wire for a purpose. I twist it between posts so it more easily catches the breeze and flutters. When I put up a new fence, I put peanut butter on aluminum foil and clip it to the outer fence in spots. Deer will smell then try to lick the peanut butter and get a good zap. There afterwards, the visual cue of the fluttering white tape is associated with the zap and they are less intent on getting inside.
Keep in mind that everything when it comes to deer is relative. There are places where a slight deterrent like "Plot Saver", which is just visual and olfactory, is sufficient to allow beans to establish. This is typically where there are equally attractive food sources in the area. It is basically the "you don't have to outrun the bear, just your buddy" approach. Where there are other good options it may take very little to deter. Where other attractive quality foods are lacking in the area, a higher level of deterrence is required.e