Interesting commentary. Some I agree with, some I do not…
Re: The Joy of Sacks…
According to statistics, (in general) sacks on 1st and 2nd Down SIGNIFICANTLY degrade an offenses' ability (i.e. ensuing probability) to make a 1st Down…
(A sack knocking a team out of FG notwithstanding…) The reality is that the a 3rd Down sack when it comes to keeping a drive alive has no more value than an incomplete pass.
Re: Under Pressure …
As for QB Pressures, this is one of the one of the most UNDERRATED statistics in football. Typically a veteran QB's QB Rating goes down by 30 to 70 percentage points when pressured. Completion % goes down and INT % goes way up when pressured.
Re: The Numbers…
NFL Passer Ratings - 2016
Clean Pocket: 99.3
Under Pressure: 64.6
Play After a Sack (usually NOT 3rd Down): 78.1
League Avg Passer Rating: 87.6
Source: Pro Football Focus