This will not work as well, since the extension has a male on one side and a female on the WDA side, hence you would still need another extension to plug the female on the 1st extension and a male on TV.Where would you plug the other long HDMI part to after you plugged one end to the TV? It would have to connect to the WDA correct? The adapter has a HDMI male plug so two HDMI males would not work hence the included HDMI extension cord. And as I've mentioned in the video, the USB extension is cheaper, but most people have no idea that a USB extension exists or would they have one lying around the house compared to a 3' or 6' HDMI to HDMI cable.
You would end up with something like:
TV(F) / (M)==ext1==(F) / (M)==ext2==(F) / (M)WDA
This actually doesn't make much sense.