not worth a whistle vs useless as tits on a boar hog

not worth a whistle

adj
  • Worthless or pointless. 

useless as tits on a boar hog

adj
  • Ineffectual, pointless. 

How often have the words not worth a whistle and useless as tits on a boar hog occurred in a corpus of books? (source: Google Ngram Viewer )