So to summarise - and use a different example:

CONFIDENTIAL - BICYCLE might tell you that the information comes from SIGINT means.

SECRET - PEDAL might tell you that the information comes from SIGINT means, involving a listening station of advanced capability.

TOP SECRET - HANDLEBAR might tell you that the information comes from SIGINT means, from a specially-equipped aircraft that is designed to eavesdrop upon selected sources.

Regardlessless of your clearance, you have to be indoctrinated into each of the levels (codewords) in order to 'legally' receive them.

Hopefully this might explain why TS classification would be sufficient for any supposed Roswell material - along with a SCI / SAP codeword / caveat.

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"For ignorance to reign, all it takes is for knowledgable people to say nothing"

Lonewulf