BOT optimizes the layout of the current Simulink block diagram.
Blocks and lines are resized and moved until their vertices satisfy a 5 pixel grid.

You can define safety zones around blocks and line; The program then moves blocks and lines, until their safety zones do not overlap. Think of blocks and lines as magnets repelling each other.

Lines can be rerouted and intersecting lines can be untangled.

Finally, the program tries to compact the diagram by moving the blocks closer to each other. Think of lines as contracting rubber bands.