No it doesn't...
Loyalty can be shown by how long someone has been with you, but that doesn't make someone more loyal than another just because they were with you for two years while the other was a year and a half (or whatever amount of time you want to put on it.)

I also have to agree with Poppo on the co-sub-leader-kind-of-thing thing.
The whole point of being a co-leader is to help your clan, having that role gives you more power to make decisions, I can't see a reason to have everyone at a level that they can make decisions, if you want something like that I'd advise just promoting one person to co-leader.

(Also from what I can see that should be Dagreja, he's active, doesn't spam, has helped the clan a lot and has stayed despite Poppo not originally liking him. He also seems to use complete logic to make his decisions and really cares about this clan.)