I've seen this set-up used by Astralis: One player is standing on the ramp to get information when the Ts are pushing. The second player uses the shown lineup as soon as contact is made to smoke between Toxic and Pillar. The third player is in Heaven with an AWP to establish a strong crossfire on the small area between Sandbags and Pillar that the Ts are forced into.

So the basic idea of this smoke is to join the attacking routes from Monster and Short into one area.