[Al Skierkiewicz]

Leav,
The FRAME PERIMETER defines the size of the robot, where the bumpers must be attached and which all parts of the robot must start the match within. In other words, the STARTING CONFIGURATION without the height dimension. The PLAYING CONFIGURATION size is defined in the rules (and hopefully Team Update #1) and would allow stabilizers under certain conditions. The least of these involves the type and material used in contact with the floor and the risk involved in deploying said devices. This would open the device to damage and give opponents a greater ability to push your robot. If those risks fit your strategy then it may be worth the effort.
For example...
<R11> During the MATCH, the ROBOT may not exceed the volume constraints of either STARTING or PLAYING CONFIGURATIONS (note: these limits are defined in reference to the ROBOT, not the FIELD).
<R14> When a ROBOT is in its STARTING CONFIGURATION, no part of the ROBOT shall extend outside the vertical projection of the FRAME PERIMETER.