I believe he meant to say "stratification", which is a term to indicate stagnant air. When I was a kid my dad would smoke in the house, and whenever the central heat or a/c wasn't running, the smoke from his ciggies would just hang in a horizontal layer about 7 or 8 feet off the floor. The air at that level was stratified...it wasn't moving. When the heat or a/c kicked on, the horizontal layer of smoke would break up, as the air coming out of the registers would mix with the air in the room.
BTW - Pleease define "statification" in the HVAC world?. I looked it up on dictionary.com, but the definition was vauge.
"use velocity to reduce statification"