I don't think it's a joke. He's either desensitised himself while making the compound, or knowing what it is has enough of a psychological effect to prevent muc

I don't think it's a joke. He's either desensitised himself while making the compound, or knowing what it is has enough of a psychological effect to prevent much reaction. (I got the latter impression watching his video on making "metal-smell") I think it smells worse with dilution too, as they noted in the video.