Generally speaking, the game goes one of two ways on my battlegroup.

Both sides race, and the alliance wins 95% of these games.
The horde only wins these games if they successfully backcap while the alliance does not, and the alliance decides to wait for towers to burn.

The alliance wipes at Galv or there is a massive choke at Iceblood GY/Tower. It becomes an attrition battle, where the horde wins 80% of these.

Overall, alliance wins 2 in 3 AV's, in my experience.




From my experience, the highest success rate as a horde boxer would be to take out an alliance back-cap team, and to back-cap two towers.
Then to use the trinket-hearth and defend/delay the final fight.