Pathfinding needed for multiplayer stratagy?

While developing my tile based strategy game I always assumed I would need path finding. I reasoned that when the user moves a unit from one tile to another the game would need to find the most efficient path. Yet this has a major drawback. A pathfinder would remove choice from the user. There will be cases where the user may want to move along a path that does not take the optimal route. Perhaps he wants to move around an enemy scout or keep out of range of artillery?

In this case he may want to dictate the movement of the unit it a more defined way. The player may wish to draw the path. This is what I am going to use in my tile based game. The real challenge seems to be making the drawing of the path intuitive.Perhaps if the unit is being moved into fog of war in this manner the player may route the path over an enemy unit. In this case I assume the best solution would be to let the player submit the move and then have the enemy unit "block" the moves progress. Many tile based games such as civilisation have adopted this approach.