Oncloggable chute together with a good airflow dynamic. These do a better job than the steel decks and alloy version of the steel deck that replaced the PT thumb latch base in 1992.
Don't forget this is the same base casting as the VC Mustang and Sports made from 1973 and they were designed to shoot the clippings upwards into the catcher and land in a pile inside, filling the catcher completely.
You will notice with the two piece rear flap, it allows you to insert the catcher without having to lift the flap at all, unlike with the single piece later on.
Your got your grubby hands on a treasure. Use but don't abuse!