I am posting information from the World of War Craft official magazine on strategies on Twin Peaks Battleground.
"Controll The Middle"
"If there's one thing you hear repeated time and time again in Battlegrounds it's that you shouldn't fight in the middle under any circumstance.. However, Twin Peaks's narrow map shape makes this a uniquely viable strategy.
"You generally want to hold the middle of the map with the majority of your group and healers while sending a tank and a healer to pick up the enemy flag. Lawerince of Shattered Hall-US says. "What will tend to happen is that the side with the better survivability will end up controlling the middle, which gives them the advantage of being able to intercept enemy flag carriers while also being able to support their own flag carrier. In most scenarios this will lead to victory."
Edarave, Cairne-US, agrees with Lawereince, but place importance on the runners' classes. "Have a large defending team with 2-3 specialized runners (druid/rogue/priest, druid /mage/priest) to chain Sprints and Leaps across field."
" While this strategy may not be particularly viable in other, wider battlegrounds, these players find it works quite well in Twin Peaks."