"Men and society tend to objectify women. When women dress immodestly, they are communicating a message that they are sexually available. You can't blame men for assuming that a woman is available if she's advertising her assets. It is much easier for a man to see a woman as a whole person if she is wearing clothes that are considered modest for her culture."
"Women are people, no matter what they are wearing. Men should take responsibility for their thoughts and actions, and no longer victim-blame women for 'asking for' objectification. What women choose to wear doesn't always have anything to do with wanting to attract a man. Women should be able to wear whatever they want without other people turning them into an object."
It is true that men, whether biologically or culturally, have a tendency in this world to see women and their bodies as commodities. This tendency has been reinforced and cemented so hard into our psyches that we hardly question it. Even feminists who take the latter stance often seem to take it for granted that women's bodies are tools for sexuality, they just believe that it's a woman's right to use their tools when and how they want, while the former stance demands some responsibility towards the broader community.
Beauty Redefined has a better way to look at it. It can be summed up in one sentence: you are capable of more than being looked at. I think they strike that elusive balance. They recognize both: that clothes send a message, and that people have a responsibility to try to receive that message in a way that recognizes a person's humanity. In my opinion, even if a girl consciously sends a message that she's ready to be just a sexual object, good people have a responsibility to see her personhood beyond that superficial message.
Of course, seeing the humanity behind someone's messages or behavior is a difficult task that requires constant vigilance. I believe that society would be improved if people embraced the deeper meaning of modesty: "Modesty is an attitude of propriety and decency in dress, grooming, language, and behavior. If we are modest, we do not draw undue attention to ourselves."
I think teaching guidelines is good! Guidelines help teach us what messages are being communicated by our choice of dress. Knowing how others perceive our choice of dress helps us make better informed decisions in how we communicate who we are. But just like any communication, we can only be responsible for our half. Just like any gospel principle, if we define modesty by the checklist we lose sight of the principle.