Did you major in retard with a minor in intentional obtuseness at Stanford?
Right.
You at once say that "teams are no more effective at passing than they were under Walsh and Siefert" and then literally in the same paragraph say that teams are having more success because they "are implementing the philosophies that Bill Walsh ran 2+ decades ago."
Well, which is it? According to you "even Walsh couldn't completely buck the conventional wisdom that you had to have "balance" between the run and the pass." And yet people are passing for more yards because... they're doing what Bill Walsh did? Well just imagine then what BILL WALSH would do TODAY if he DID WHAT BILL WALSH did but then also DIDN'T DO WHAT BILL WALSH DID (ie, succumb to that conventional wisdom fallacy)?
No...that's not what I said. I said MORE teams are having better TD/INT ratios because they are implementing the Walsh system. However, like Walsh's and Siefert's teams, most teams have been unwilling to exploit this success by passing the optimal number of times (at least closer to 2/3; maybe more). It is likely that only a few are able to succeed at such a volume, just as only a few would have been able to do so in 1995. But those who have done so, have put up big numbers.
Take a deep breath, and let me see if I can explain it a little more slowly.
Let's take the 2011 New Orleans Saints, the team whose QB set the all-time single-season passing yardage record. This team is not significantly more effective at the passing game than was, for sake of example, the 1992 49ers (you can say the same thing about several Montana or (!)Ken Anderson teams. What do these things have in common? Hint: not awesome rules).
Saints: 472 - 662 (71.3%); 5347 yards (7.8 ny/a); 46:14 TD/Int (3.29:1)
49ers: 319 - 480 (66.5%); 3880 yards (7.6 ny/a); 29:9 TD/INT (3.22:1)
The obvious difference here is in total passing yards, and thus pass attempts. Your theory would suggest that the reason Siefert and Shanahan didn't pass more is that they somehow determined that somehow they had reached the optimal number of pass attempts to maximize passing efficiency. Not just that, but that any passes beyond 480 (with exceptions such as situational time-killing) would net fewer yards than a rushing play. Of course, this was not going to be the case. The 49ers averaged 4.8 yards a carry (nice season, Ricky!); pretty good. So maybe this is why George decided to grind it out a little. But this year's Saints were even better running the ball, at 4.9 yards/carry. Still, the Saints recognized that their most efficient play (just as it was for the 49ers) was the pass.
So, the Saints decided to pass the ball 61% of the time.
The 49ers decided to pass the ball only 49% of the time.
The 49ers had devised a devastating offensive scheme, yet decided to underutilize it. What we are now seeing is that the teams with these weapons are now maximizing them.
In 1984 when Marino set the yardage record, leaguewide, passes represented 54% of all plays. In 2011, that number had only inched up to 55%. People are still not throwing the ball, even in this AWESOME passing environment. What we are seeing is not a league-wide videogame-like ability to throw the ball with ease. What we're starting to see is
the teams with the elite QBs recognizing that the best way to utilize those weapons is to throw the ball early, often, and on safe horizontal routes. The rest of the league continues to plod along running the ball and throwing vertically when they throw, because they lack the system, the talent, or both.
The "rule changes" are much less of a factor than is this recognition. There have always been QBs in the league who are capable of doing this, yet the conventional way of thinking hamstrung coaches into believing that no matter how good their QBs and receivers, they had to feed the rushing beast.
The big rule change happened after the 1978 season. That's when the game changed. Since then, it's just been a slow process of developing what is the optimal method of offensive football.