[dragonwriter]

> But ... many men are absolutely clueless and will never get that signal.

Which is irrelevant to the existence of sexual harassment, a hostile work environment, or the employer's tort liability for failing to address those things, and so not particularly relevant to what the employer rationally should do in the situation.

> So I think part of this discussion needs to acknowledge that you can't write HR policy that will satisfy everyone.

HR policy isn't intended to satisfy everyone, its intended to maximize benefits and minimize costs to the employer of its relation with its (current, past, and potential future) employees, and an important area of cost minimization it deals with is costs of litigation and ensuing legal liabilities.