They have been running lots of cover 1 man and cover 3 with a mix of man and zone concepts the past 3 weeks. They have been blitzing more too. People also need to recognise the difference between zone coverage and what is properly called "soft zone."
They have had some issues in zone coverage looks (whether standard or soft) but their numbers in man are worse. And yet every time something bad happens it is greeted with "that blasted zone coverage!"
It isn't the fundamentals of the scheme that are the problem. It's the way they are calling it and executing it that is the issue.