Yeah. Let us say you have 200 militia. If you assign them all to one general and while the game is still "thinking" you try to assign them to another general it will give you the zero militia on the second general. It does not matter the troop. You get it a lot while loading up troops before sending them home from adventures.
Flash is wonderful... add in some lag and/or older equipment and voila!
Sometimes tasks like loading troops takes a few seconds to 'register'.
“Many that live deserve death. And some die that deserve life. Can you give it to them? Then be not too eager to deal out death in the name of justice, fearing for your own safety. Even the wise cannot see all ends.”