Has any body ever done this work before?

[jmvillelabeitia]

Watching some games from the 80 I found out that QB were out of the pocket they still had to throw it to an elegible receiver, they could not just throw it away as they do it nowadays. I found out this rule changed in 1991, before QB could not do it. Joe Montana was playing with the Chiefs and some one told him to just throw it away in that case.

Has any body ever done any study of how this rule changed the way the games are played? Since then the worst scenario is a lost of down, but before this they faced intentional grounding plus lost of downs, plus not to speak about the risk of throwing an interception.

Special thanks