Being Honest Vs. Being Effective

So after discussing some of the harassment that apparently happened at WorldCon, a friend of mine on Facebook said this:
“These cons seem like horrible places.”
The problem is, they often aren’t.  Talking with a lot of my female friends, most of them didn’t have any incidents of note at the con that removed their ability to enjoy themselves (at least not that came up in conversation, and my female buddies aren’t shy about bitching about creepers).  I’d tentatively venture to say, knowing that I’m a guy and hence don’t get the kind of con-destroying harassment that females are prone to on a regular basis, that most people at the con actually just went and had a good time and weren’t made miserable by sexual bullying.
But some were.  Those people deserve safer spaces.  The only way to make these spaces safer is to publicize these incidents so we can rectify them… but we do so at the cost of making cons seem like a terrible place to be.  In that sense it’s kind of like New York City – which, yes, has some crime, but the focus on fixing crime makes it sound like when you step into NYC you’re automatically given a voucher for a mugging.
So we make cons actually safer by discussing bad behavior in public, but make them sound far less safe than, say, the fun cons of the 1970s when Isaac Asimov was pinching everyone’s ass and editors were trying to fuck young girls in elevators. So you make it better for people who attend while potentially driving new attendees away.  And I’m not sure how you fix that.
Likewise, during the Democratic National Convention, Saladin Ahmed was complaining on Twitter that from a practical perspective of international politics, Obama really isn’t all that different than Dubya.  Which is true, if you’re not in America.  I mean, once my family was blown to wet meat in a predator drone strike, I’m not sure I’d go, “Oh, thank the stars that explosion was authorized by a Democratic President!”
All true.  But still, there is a distinct difference between what Obama wants to do and what Romney wants to do in a lot of other areas.  Saladin’s absolutely right to complain, but on the other hand if Romney won, I don’t think he’d be that thrilled… and reminding people of Obama’s terribleness at a time when I think he really needs to win is counterproductive for victory, but productive for reminding us to hold our President’s feet to the fire when it comes to all of those human rights he claimed he was for back when he was running in 2008.
I don’t have a good answer here.  Sometimes, being outspokenly honest has unintended backlash, even if the results are good.  I like to point to a solution here, but in these cases, I want the cake and edibility as one: for people to publicize bad incidents at cons while making them seem attractive to attend, for Saladin to point out flaws in the Democratic party while still encouraging voters to get out there.  But I cannot.  And I’ll prioritize honesty, but acknowledge that sometimes it’s a bitch.