This again. It seems to me that it is not, in fact, all that hard to avoid propositioning one's students--and that, moreover, if one is so endowed with chili peppers that the students proposition you, it is equally not that hard to defer certain unclothed activities to a more appropriate moment. That moment being when that student is no longer in any way under your control. "But wait!" you wail. "You're asking me to put off coupling for two years?! The student will have lost interest by then!" And so will you, I imagine, which is rather the point. If this is actually a grand passion that involves violins, sunsets, and spontaneously-blossoming roses, then no doubt you can take the necessary, if potentially cumbersome, steps to ensure that said grand passion can be pursued without violating your professional integrity or the student's rights.
Now, I admit to being unsympathetic because, in fact, a number of the faculty-student sex stories that have come to my attention have had negative repercussions for other students. In other words, this is never entirely about two (or more?) star-crossed would-be lovers; it's about the other students and even, yes, one's colleagues (who may have to pick up the pieces if something goes, to use an esoteric technical term, disastrously kaflooey--and, of course, I can think of at least two departments in the 80s and 90s that imploded over sexual harassment problems). Moreover, while I do in fact know plenty of "old-timey" stories about professors whose hands wandered on a regular basis, and whose female students shrugged and put up with it, it's never been clear to me that said students found such behavior precisely entertaining. They "put up with it" because, pace Prof. Kipnis, they appear to have felt that they had no choice in the matter. Now students have more choice in the matter, and strange as it may appear, many of them don't feel like being fondled, propositioned, or otherwise handled.
Finally, and I admit that this is unpopular in some quarters: one of the downsides of this profession, as with any profession, is that you don't get to be yourself, to indulge yourself, or to do whatever, er, yourself feels like whenever it pleases you. Part of that not-being-yourselfness means that you treat your students as students, and not as sex objects. Their lives will be full of plenty of "vulnerability" without your assistance.