Three great Head Coaches that could not get their teams to a Super Bowl for one reason or another. All three were conservative offensively in their approach, however, Allen had Ted Marchibroda as his OC or Offensive Coach back then and Knox had Ken Meyer, who was great in 73, however, seem to become more & more conservative until he left to become Head Coach of the 49ers in 1977.
John Robinson started with Jimmy Raye, however, after that served as his own OC and Dieter Brock spoke about how archaic the Ram passing game was under Robinson, it wasn't until Robinson hired Ernie Zampese & Norv Turner did the passing game evolve. Many heartbreaking losses under Knox & Robinson as I was too young for George Allen.