In unit design, tool tips lock into the first location they appear and thus appear in the wrong location for any tool tip that isn't the first thing you mouse over.  For example, if you mouse over the attack strength of the wooden club, it displays properly.  If you then mouse over the attack str of the spear, it displays the tool tip over the wooden club.

If you then mouse over the troop training time for the staff or spear, that will also lock into the location that you first hit.

I apologize for not being to explain it better.