TOPIC: cron doesn't send

By default the cronjob doesn't send e-mails. If I use command line, it echoes the correct email addresses though, but no emails are send.

With some debugging of cron.php I see some commented lines like: //$sent = $dt_mail->Send();
I'm sure for some good reason?
But if I make #718 available (removing the double-/ the emails do get send out.

Is this a bug? Or should it be commented? And should the send be done elsewhere? If so, why doesn't it work?