Its an annoying issue caused by wifi interference with badly insulated USB 3.0 Devices who emit an electromagnetic field at the same frequency as 2.4Ghz router.
It's a problem with the norm "USB 3", and tons of peoples had similar issues over the year on other mac and pc.
It's well documented and known :
http://www.intel.com/content/www/us...al-bus/usb3-frequency-interference-paper.html
A quick google search for something like "USB 3 kills my wifi" show that not just macs are affected.
However, the question is if the new MacBook Pro is particularly poorly designed in a way that make it worse. Honestly I think we need more than this guy video for that. (because just the position of the device can also affect that. Sometimes just moving it a bit will make the difference between having wifi and having no wifi. From my own personal testing, sometimes I was able to catch Wifi by moving the computer around. So the fact that this particular Dell worked with that particular accessory doesn't really mean the MBP will be worse in all situations.
Basically Intel knew about it from the start, but I guess they estimated that peoples are moving to 5Ghz wifi. It seems that's not the case.
