The video was made on window glass which is strongly hydrophobic. I chose those windows intentionally.
If you watch the video carefully, you'll see that the water running down the glass behaves in exactly the same way for both sets of jets. You only get the curtain effect on hydrophilic glass. On hydrophobic glass, the water always seems to run down in channels.
On hydrophilic glass, pencils and fans both produce the curtain effect, so there is no real difference.
The difference, to my way of thinking is on hydrophobic glass. With pencils, you have to watch very carefully, it takes a lot more effort and is slower. With fans, you can be absolutley 100% sure that the glass has been rinsed.