should you dump it back in the motor is tough to answer...
how many miles on the oil, are the additives used up?
how many cold starts on the oil which contaminates it with water and acid?
in this case, with a brand new build that's bleeding 16oz in just 50 miles,,,,I'd probably save the oil to use in my older than dirt lawnmower that does puff abit of smoke...
(more "new" oil additives added to his motor can only help)
if there is say only 2oz in the jar after 50 miles (pcv isn't the main problem),,why not,,2oz diluted into 160oz in the pan (5 quarts) won't hurt....