ScottHope: The lines will stop, if the shot is held long enough, at a point which is at the same position as when maximum power is applied.
After some experimentation, I tried to accomplish what you've described above.
In order for this to work for me, I can use no more than 1/2 of the club's rated power. By this I mean that if my backswing arrow is at 50% of the meter, I get some movement of the forgiveness bars... all the way to where they'd be starting out if I was at 100% power.
In fact, the bars move proportionally (as they should), but at a greatly reduced amount.
For instance, at 75% of the backswing, they'll move more (about 5 pixels) than at 90% of the backswing (where there's only about 1-2 pixel movement), but nowhere near the distance that they should be moving.