Clearly this is going to depend on a number of variables, such as particulars of the scene as well as the target audience. However, I'm pleased to hear so many voices sharing my sentiment -- showing up fully clothed and remaining so at least until thoroughly messed is preferred. My view is almost diametrically opposed to htstn1's perspective. When I see a model in swimwear or obviously inexpensive attire, as if she were expecting a messy experience, I get far less of a charge out of the scene than when formal attire or a really nice set of street clothes are made thoroughly messy.
I would not assert that either one of us is clearly right or wrong. (Though I would argue that it is wrong to write about this in absolute imperatives, as if it were somehow a failure to produce media that is not precisely designed to accommodate one's personal preferences.) Clearly the market can bear examples across the whole spectrum from "always nude with explicit sex acts" to "prim and proper attire from start to finish." Personally, I enjoy both extremes. Even so, I find the middle ground of swimwear, lingerie, and very skimpy clothes to be a sort of "worst of both worlds" lacking the appeal of either nudity or a proper elegant outfit enduring wet and/or messy treatment.
I suppose for me the ultimate scene (short of an event involving my own participation) would feature a group of young women in fine dresses or blouse and skirt ensembles gently progressing from playful dabs of mess to a colorful and uninhibited foodfight followed by tearing one another's clothes off and having a slippery glistening lesbian orgy, the camera silently documenting all of it. Yet even then, my interest might be more concentrated on the early phases than the finale.
I suspect it has something to do with vanilla sexuality being much less rare in my life than the experience of feeling and seeing a beautiful woman getting wildly messy in one of her favorite outfits. Then again, it may just be that, in the absence of a strong emotional connection, my conventional sex drive is not as easily engaged as my fetish-response. Whatever the case, I suppose I count as another vote for the "start out fully clothed and stay that way until you're good and messy" preference.
Regards,
messydom