I'd guess it's the latter, we need to rotate them through.Well, he is...and he isn't. He's bringing in the young guys, but only at the expense of other young guys. It's never a young player coming in for an experienced player who's out of form. So either the experienced guys will never be dropped regardless of form, or the MC simply don't want to play what they consider to be too many younger guys at the same time.
I personally think it's a little of each, but I'm only speculating of course.