Conley's study included four parts:

1) "Using a person-perception paradigm, I assessed people's impressions of women and men who proposed a casual sexual encounter in the same manner that confederates in Clark and Hatfield did. Women and men agreed that female proposers were more intelligent, successful, and sexually skilled than men who made the same proposals." In other words, the particular form of the proposals in Clark and Hatfield affected people's assessment of the proposers. Perhaps proposals made in a more socially acceptable way would be viewed differently. After all, what percentage of real-life casual sex follows a blunt approach from a complete stranger? Normally one at least starts with a few minutes of casual conversation.

2--3) "I demonstrated that the large gender differences from the original Clark and Hatfield study could be eliminated by asking participants to imagine proposals from (attractive and unattractive) famous individuals, friends, and same-gender individuals. Next, I assessed factors associated with likelihood of agreeing to the casual sex proposal. The extent to which women and men believed that the proposer would be sexually skilled predicted how likely they would be to engage in casual sex with this individual."

Conley's conditions do seem too strong to me ("guaranteed positive experience" or "experience which, even if not that great in itself, will be something to brag about for years").

4) "I examined these factors in the context of actual encounters from the participants' previous experiences, and the results were replicated in this context." Seems valid to me, though I'd like to hear more detail (I don't have access to the full text).

My opinion: "Women are less willing to have casual sex because they think it might not be a positive experience" doesn't contradict "women are less willing to have casual sex" at all. Indeed, Clark and Hatfield say, "We know that this is so. We are not quite sure why this is so.... Of course, the sociological interpretation---that women are interested in love while men are interested in sex---is not the only possible interpretation of this data. It may be, of course, that both men and women are equally interested in sex, but that men associated fewer risks with accepting a sexual invitation than did women.... Also, the remnants of the double standard may make women afraid to accept the man's invitation." Clark and Hatfield wonder about the reason for this, and Conley makes attempts (some of them flawed) to figure it out. The problem I see is that everyone is so eager to interpret new results as overturning old ones instead of as refining or elaborating on them.

Edited to add: The relevant part of Eagly and Woods. "For example, the classic finding that men are more likely than women to agree to have casual sex with a stranger depends on the social context and the sexual opportunity. No sex differences in interest in casual sex emerged when the potential partner was a famous, attractive person or someone reputed to be sexually skilled." This is not a claim that the original study has been overturned. Clark and Hatfield's proposers were not actors famous for their physical attractiveness, not were they locally famous for their sexual prowess.