[Norfleet]

Originally posted by Graeme Dice:
I'm not entirely certain how it works now, although I think I might have seen undead units dissolve when I couldn't think of another reason for it.

I'm quite certain that mindless units remain intact and undissolved as long as ANY friendly commander on the field retains the ability to control them, regardless of what his leadership rating is.

However, said undead also tend to be rather brittle, and as such, are prone to just dying. Perhaps you thought they were dissolving from lack of leadership, when, in fact, they were just being killed by something not immediately visible.