Not so much about the tree, but whether you are running an index or all out. If you run all out then use stagger to stage shallow in the beams when you qualify, this lets you get a run at the start beam before the timers hit and will improve times and stage deeper when racing to shorten the track.
There is a debate on whether it helps with index or not. If your class does not allow DEEP STAGING the there is not that much bennifit to offset and the axle should be straight up and work on your staging to get it consistant. I race 7-0 and deep is allowed and I also run 2" of offset.My driver goes in deep everytime and what this does is puts the car in the same spot within an inch everytime because he stops when the light goes out and the track is as short as it can be without fouling.By being in the same spot every time eliminates a varible that can affect my times. With a 21" tire and 2"offset, by the time both beams just come on till the time one redlights is around 18" so going in deep cuts around 10" off the track