A singer-shamwriter is a singer who is labelled a singer-songwriter by their record industry boss in order to boost their appeal by appearing talented, cool and down with the kids. In reality however, the singer-shamwriter couldn't tell the difference between F major chord and an A minor chord. All their actual material is written by really talented individuals who just happen to be fat and ugly and who therefore one wouldn't want to see on Saturday morning television. C'est la vie.
Katy Perry is a singer-shamwriter.