No, calle has a point.
Perhaps the guy in the video doesn't know english that well but surely he knows "be" is spellt be and not "b".. it's just lazy to not do that right lol.
The same as "n" and "bcoz", it's just lazy and makes the tutorial not seem serious at all. To me it feels like most things that are explained are obvious and doesn't really go in depth, maybe it's just me though.