RFC2119 keywords in registration requirements

[Julian Reschke <julian.reschke@xxxxxx>]

So,

while getting IETF LC comment for httpbis, one reviewer complains about 
the use of RFC2119 in registration procedures, while another one 
complains about the lack of them in a different place.

Can we please clarify what's the right approach?

Best regards, Julian

/me thinks RFC2119 do not belong there.