As a person who has HSV and partnered with someone who does not have it AND as a sexual health educator, I thought I'd throw in my 2 cents.
1) I have also wondered about the seemingly contradictory stats on discordant couple infection and overall herpes infection especially given the common message that most people who get herpes get it from a partner with no symptoms. My theory is that the difference betweeen knowing you have herpes and not knowing plays a significant role. That is, if you know you have it and know what to look for, you know better when to NOT have sex with a partner AND can take Valtrex. Also, studies of discordant couples follow couples who are in at least somewhat serious relationships (I gather since they can be followed for the length of the study) and thus probably more comfortable with each other and communicate much better than casual partners and thus take better precautions against passing H. If a person is not sure if they have H (or even know they have it) and they are hooking up with someone casually, it is probably less likely they'd be extra careful to pay attention to any signs that they have or are getting an outbreak AND less likely that a person will ask if their hook-up has an STD. Thus I think it makes sense that these two stats are so different even if on the surface they seem to be contradictory. (Not to mention that alcohol probably plays a not-so-insignificant role in more casual sex.)
2) Though I see your logic, don't see this theory working. Though I might theorize that while it wouldn't prevent H, it might make a first outbreak less severe if you give your immune system a head start. I don't know, just a thought. Not something I'd ever tell a student.
And just a few more cents thrown in---I am glad to hear you are not running for the hills because your partner has H. Good for you! I was ready for my then-boyfriend (now husband) to run when I told him but would have been heartbroken and devastated if he actually did. I take Valtrex like ever other day and have not had an outbreak in over 3 years and have not infected him. We are very much in love and have a wonderful open and strong relationship. it would have been a real shame if that had been thrown away just because of some skin infection that has come to be SUCH a non-issue. As far as your fear of the unknown--I won't lie, my first outbreak sucked and was painful. But I started on meds right away and basically just stayed in my house with a bag of frozen peas on my crotch (which helped a lot). Of course all this was on top of my emotional devastation of getting H from a partner I was just not that into anyway and the whole fear of no one ever wanting to be with me again etc. etc. But you would not have that element of shock and fear of being alone. Since then the couple outbreaks I have had have been the equivalent of a pimple or two. My point is, don't let fear of the possibility of a few uncomfortable days ruin a great relationship. besides, lots of people get mild first outbreaks anyway. And even if you did leave your partner, odds are your next partner would have herpes or HPV anyway. And maybe this time, they wouldn't know or wouldn't tell you.
Just my thoughts. Take what you will and best of luck to you!! And good for you for educating yourself