Sigma said:A related question: can tower shields block LOE? So, if in this example the goblin were hiding behind a tower shield, could he or the space behind him be targetted by the spell?
That would be one big tower shield, especially for a goblin.
5'x5' is pretty big, and the tower shield is at best maybe 3' wide (and thats being generous). With a mantlet (or movable wall basically, you could stop it, but thats like saying you can't cast throug a closed door.