One of the first ways to ensure a draw (doesn't work so well now) was if it's mid-game and your opponent knows you cannot kill his LeBeau'd AD enough times in one turn to close it, and you have no way to return it (except for a backup SC, such as Assassin)... he can simply rest every turn. You cannot damage his LP since he refuses to put out units for your ranged ones to take a crack at. hunthunthunt has done this to me once, and it was one
very boring game... resulted in my first and only draw

.