[1fastredsc]

The collar can collapse, but only collapse. In a set state, it's no different than a normal valve. When open, the collar will only move if the cylinder pressure is still higher than that of the port. Therefore if the cam opens it early, but the exhaust is still pressurizing to leave out, the it continues to seat against the head even though the valve is attempting to open. When it's still open but attempting to close, if the air is traveling at a slow pace, and assuming there's enough duration to create blow back, then the positive pressure in the cylinder during the beginning of compression will cause the collar to collapse and seat early eliminating blow back. This is why in theory this is amazing, but the practice is still limited which sucks. I guess we'll all have to wait a couple of years before this becomes fully reliable and available.