off the hook vs unobstructed

off the hook

adj
  • Of a telephone, having an open connection; not hung up. 

  • Performing extraordinarily well. 

  • Relieved of a duty, burden, responsibility, or pressure. 

  • Fresh, cool, trendy, excellent, incredible. 

  • Of a telephone, ringing frequently. 

unobstructed

adj
  • Not obstructed. 

How often have the words off the hook and unobstructed occurred in a corpus of books? (source: Google Ngram Viewer )