Very inexperienced depth.
It generally takes young props a few years to really hit their stride and at some point our less experienced props are going to struggle because they can't handle the weekly grind of the NRL.
Burgess at his best is one of the best front rowers in the comp and Seibold seemed to be able to get him to pull his head out of his ass and start performing. He also brings a lot of experience. Some people are underestimating just how valuable that will be in the front row. The rest of our forward leaders such as Gillett, Glenn and Macca won't be able to pick up the slack when the young guys are struggling. They will be too busy with their own jobs and they don't play in the front row.