I didn't realize there was a video, sorry.Wow I have no idea were you able to see the video?
I have an Egyptian fayoumi who started growing at six weeks but I knew that that was normal for the breed.
They are great at being hyper and alert. But if you get them (from my experience) from hatching mine get on top of me and are huge lovers.I didn't realize there was a video, sorry.
It just depends on the chickens, though some breeds are early or late bloomers.
Are Egyptian faumis as skittish as I've read they are? They are such cool birds.