Deconstruction resists authority. You are applying this approach when you look at the structures and seek to determine the validity of the ideology which informs them beasue you question whether the structure is telling the truth about the world. As this occurs, everything comes into question. Any institution which has authority coems into question. It becomes a negative practice when this leads to the idea that there can be no truth at all and that it is not possible to develop valid beliefs about the nature of the world.
Nothing is seen as 'naturally right'.
However, it has also led some others to become more critical of texts that are not normally questioned such as advertising material and other sources of information in the media. It has 'demystified' binary oppositions. These binary oppositions are not 'truth' but 'myth', which speaks it's own truth which must be discovered. AS A GAME, this demystification leads to a separation from the social group that accepts the myth. The past is imagined differently and all minority and dominant groups are studied rather than just dominant groups, in order to help one understand the text.