Yes a well phrased question does help - so what is IGC?
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
It may be used to check the quality of materials, I have not, so far, seen this method, but some videos relied to this method available in YouTube. I think SS materials can be checked whether to proof it is SS.
Maybe the OP should post in the appropriate forum for better answers.
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)