Any head coach who DOESN'T "interfere" - as quickly as possible - with any part of the program that isn't working well is not doing his job.
Whether that be on the practice field, in the staff meeting rooms, during game day prep, during schematic meetings, recruiting processes, or - when needed - with changing the composition of the staff.
That's their job.
Over the last 3 years, PSU's offense has averaged 22 points per game against ranked teams. For comparison, Michigan averaged 33 ppg, OSU 32.5 ppg against ranked teams over that same time (FWIW: Prior to coming to PSU, offenses where MY was the OC averaged 35 ppg against ranked teams).
The concerns certainly did not become obvious just last month. Right?