U2414H, Mac Book Pro, DisplayPort 1.2 blank, resolved

I'm posting this here in the hope that it gets indexed by search engines and other people can find the answer I spent a couple of hours searching for without any luck.  I should say at the onset that I'm generally very happy with this monitor - love the super-thin bezel, very good image quality, easy to set up and a great price. However, most of this post is going to be a complaint and warning to others. I was told, incorrectly, that my early-2011 Mac Book Pro 15" mini-DisplayPort supported the DisplayPort 1.2 protocol. Turns out it doesn't. So when I enabled DisplayPort 1.2 the screen went blank, as the instructions said it might. No biggie, you'd think - just get the on-screen display (OSD) up again and either disable DisplayPort 1.2 or do a factory reset. Thing is, you can't get the OSD up until a source is correctly connected to the display. Which means that you can't either disable DisplayPort 1.2 or do a factory reset, which you want to do because you can't connect correctly to the display, until you correctly connect a device to the display. And so on and so on.

There is no other way to do a factory reset, therefore the only way for me to reset the monitor is to go and buy a mini-DisplayPort-to-HDMI cable so I can connect to the monitor that way and do a factory reset. I confirmed this with a call to Dell tech support, too. I can't imagine quite how the thinking went when designing the firmware. How on earth do you design a monitor where the only way of doing a factory reset is when a device is correctly connected? A major flaw, but it'll only affect you if you don't know this in advance, hence this post.

It would also have been clearer if the warning had said "this may make your screen go blank which, until you have another cable to connect to it via HDMI, means that you essentially own an expensive piece of plastic.