The field this year has some semblance to Ultimate Ascent's field, with large field objects creating chokepoints. The chokepoints this year are the two corridors where robots can exit their key.
Optimally played defense will make it extremely difficult for boiler-scoring robots to leave the key after their cycle, as IMO, playing defense on intaking robots is more important than defense on scoring robots, as accuracy matters less than volume of fuel fired.
A blue robot shifting between these two positions can significantly disrupt an opponent's cycle time, and even has the potential to entirely lock them out of acquiring new gears or fuel to cycle.
http://imgur.com/a/NA1uK