I hear you and I think it can work with the right player.
I spent 35 years in the Army and have studied leadership closely. What I have leaned is that you can coach leadership, but you can't make a leader. You can appoint someone - but that just sets a low standard that others will emulate.
Let me caveat my next few points. I am not involved with the club or playing group so everything I am about to say is from what I have heard from AD in interviews, from third hand information and my observations of him on the field.
From what I gather, AD does all the things off the field and around the club that demonstrates that he has leadership potential. He also clearly understands what leadership is about and has great intentions. The litmus test for leadership is when you operate under duress. Fortunately players are under duress every week so you can confidently identify leaders.
I have seen plenty of parade ground soldiers wearing rank and who look great in a pressed uniform. They say all of the right things to all of the right people and are placed in charge of the lives of young soldiers because, on paper, they have the right leadership qualities. I put AD into this category. Unfortunatley, some of these guys (and girls) completely fall apart on operations and the real leaders are unearthed.
In our game you can test leadership weekly. Unfortunately AD, for all his good intentions and desires, he is not an on field leader. He tries too hard to lead and takes on too much responsibility and in doing so misses all of the things that would make him excel. He doesn't do the 1%ers, he fades out of games and appears disinterested and his basic skills in defence, at 5/8, are appalling. So although AD has some very good leadership traits; he can't be a leader.
You can appoint him as a leader, but you will get exactly what you promote. Players won't do the 1%ers because the Captain is not setting the standard. He can't pull others up, because he isn't doing it himself. If he wants to be a leader he needs to take a good look in the mirror and check the reality of what is staring back at him. If he works hard, he could be the Tigers Captain - but he needs to do a lot of work.
Leadership finds the individual - not the other way around. If AD can develop himself as an individual - leadership roles may follow. But for now he is a follower!