In all the time I've been using the internet there is only ONE thing I've ever seen that 'really' disturbed me... That being the video of the hostage beheading that was circulating for a very short period (don't ask).
Of course there have been plenty of things I've seen that have annoyed me (beatings, abuses, lies, etc) but that one video was the only one that made me wish I hadn't have seen it.
Yes when I was younger I did look at some 'bad' pictures of the ladies; but what guy can honestly say that when he was younger he never did? Of course it is not something I still take the time to do (or should I say waste the time).
I don't think seeing such pictures (porn) when your a teenager really 'damages' you, or at least not me. It might slightly skew how people view sex (sex for sex, not relationship orientated). But guys kind of have a messed up conception of sex at that age with
or without viewing porn.
If I was a parent I'd unblock the internet for any child 12 and up. Teens should be able to explore and learn at their own pace... If they feel they want to look at some adult pictures then so be it; there are worse things. All the parent has to do is make
sure they stay in touch with reality and don't let it go too far (although I'm not sure 'porn addiction' is a real condition).
On a side note; what if a teen wants to read up on STDs and contraceptives? Will this software block that too?