refraining from force/coercion is something quite separate from the concept of preferential attraction in general. i don't think it's trying to set up what would be a false dichotomy so much as enforcing that separation.

it doesn't need to be a perfect definition because it will never be a perfectly defined concept. there's too much variability in factors. the definition gets the point across and actually expands to point out further that a lot of what we tend to think of as child molestation ought to be seriously reconsidered and perhaps placed in a different category that is not condemnatory, based on the contributing factors that are variably good and bad, and also on the results which are also variably good and bad - such as the lack or presence of any malicious behaviour and altruistic concern in a way brief enough to fit inside a small paragraph. alright.

to your second point: i don't think there needs to be a preferred one. if one or the other is present - let alone both - then there is at the very least a serious cause for concern to the child's gaurdianship. at the worse end of the spectrum those are red flags for actual damage - it's not something we want to play coy about.

in your given scenario about mutual "molestation"... the same rules apply.

measuring "altruistic concern" is perhaps the more difficult task compared to interpreting the presence of any malicious behaviour (assuming we are leaving stereotyping and prejudice out of the equation)... but i don't see that being more ambiguous is reason to exclude a factor. to be fair, there are many more factors. you could write a lengthy essay about what constitutes molestation. i would argue that the examination of that gives way to an examination of the presence of consent - an at once simple and highly complex topic which is what makes it so hard to pin down exactly. we can get a pretty good idea of it just by intuition (most of us, i assume), but the integration of that into a set of rules and policies of conduct to account for less empathetic types will prove infinitely difficult, since some individuals take advantage in ways we could scarcely imagine.

so we have to settle for a "good enough" definition that has the best (however you define that) exclusion versus inclusion rate (does the best job of sorting the babies from the bathwater) and do a very careful job of sorting out non-threat from threat. it's never going to be perfect... but the current system fails far too often and is far too draconian and is implemented much, much too unfairly to continue to justify in light of the extent to which that system is actually effective in deterring and dealing with real threats.

~ loom