In a typical overcharge for a residential split-system I understand the Discharge and Suction Pressures are higher than normal. The Superheat is low because of increased velocity, having less time to absorb heat from the heat load after leaving the latent heat zone. Subcooling is more than normal because there is more liquid in the condenser being exposed to ambient. Current draw in increased because the compressor is working harder to move more refrigerant.
So, WHY IS THE SUCTION LINE COOLER THAN NORMAL? Is it not because of the velocity, and the fact that the gas has less time to be exposed to the heat load, which would raise it's temperature and increase the superheat?