through his actions and words, particularly as they pertain to football, other sports and the athletic department in general. The fact that he may be overruled by his bosses doesn't detract from this fact, unless his decisions were not routinely adopted (which they are, from all appearances).
Swarbrick never would, and wouldn't have to, resign to protest the administration's acceptance of football mediocrity. He could keep his job while trying to change the administration's viewpoint, something he's uniquely positioned to do by virtue of his job. Instead, he's made public remarks which explicitly articulate and personally adopt all-too-low expectations, and has expressed mostly unqualified satisfaction with Kelly's performance in relation to those expectations.
The mere act of retaining Brian Kelly indicates that ND is perfectly happy with his middling performance. But surely Swarbrick is capable of phrasing that retention in terms that suggest Kelly hasn't met expectations -- e.g., "while 2014 hasn't turned out as we hoped, we are pleased that this has been ND's best 5-year period in nearly two decades, and we remain optimistic that Brian Kelly will have ND contend for national championships on a regular basis in the coming years." Instead, Swarbrick only mentioned national championships as a desire, not a goal (they're not synonymous), and said that Kelly's 5-year performance has met Swarbrick's own expectations.
Significantly, there wasn't even a hint that Swarbrick's expectations for the next 5 years will be higher than they were for the last 5. Somebody has to change that dynamic right away -- whether that be Swarbrick on his own initiative or by decree of his bosses, or whether it's another Athletic Director.