> My issue with mandated ranges is how to require the range to be narrow enough, without preventing the candidate from negotiating?

So few candidates so rarely have the power to negotiate above what the hidden range already is, that this is a non-issue.

We really shouldn't be deciding policy based on the outliers, besides which those people (the outliers) that can dictate a number higher than the range already set aren't hired from advertisements anyway, making the whole "but we can't do this because it would affect those who don't apply respond to job ads"...