2 parachutes is bad. Those are military somewhere.. maybe South America. Yellow jump suit indicates a student.
Dual deployment actions is to ensure the canopies are separated, then clear airspace and release the main canopy.
Dual canopies, the parachutes will oppse one another, then with the jumper as the fulcrum point, they will rotate and face downward, then accelerate.
Some demonstration teams will do inventional downplanes as part of their canopy relative work.
At about the 7 second mark, the two jumpers join to create a downplane... this is what would occur with the single jumper.. I know a guy who survived a hardware downplane impact. Took him a very long time to get rebuilt