[The X Phial]

In fact, I would argue that Boromir was too loyal. He let his loyalty to Minas Tirith and pride in his own abilities, and those of his city, cloud his judgement. He let it be known early that his first loyalty was always to Minas Tirith. I think the argument is for loyalty tempered with reason and humility. Sam follows Frodo out of loyalty, but he also knows his own weaknesses and uses his own sense when he needs to.