Oh I have no doubt he could still own the record book if the league hadn't changed the rules to accommodate quarterback and receivers as they have. Receivers were MAULED and holding/pass interference wasn't that unless it blatantly obvious. Defenses today will get flagged for roughing the passer for simply giving a quarterback a dirty look. Marino was one of a kind. In my biased opinion, there will NEVER be another quarterback like Marino. What he did...he revolutionized the quarterback position. Everyone wanted a Marino on their team but since there will never be another Marino, the NFL had to change the rules to give the optics of having another Marino. Transplant Brees, Rodgers, Favre, Manning and yes, even Brady...in their prime to Marino's era and they wouldn't perform half as well as the NFL rule changes have allowed them. Marino was THAT good!
He falls a bit short of 6000 yards and 60 TD's. Marino's 1984 season adjusted to 2019 would give you 5802 yards, 54.3 TD's and a rating of 129.36. And just so there's no confusion, those numbers represent how "impressive" Marino's 1984 season is using 2019 numbers. They don't tell you whether he would actually have those stats in today's game.
No way to prove it, of course, but for my money, he'd have been over 6,000. Out of curiosity, what kind of adjustment is applied there? His % of totals over the average for his time, compared to that same % over average today? Something like that?
I just multiplied by the ratio of league averages. For example, Marino had 5084 passing yards in 1984, the league average in 1984 was 3294.2 while it was 3759.4 in 2019, so the ratio is 3759.4/3294.2 = 1.1412, and multiplying 1.1412*5084 = 5802. https://www.pro-football-reference.com/years/1984/index.htm https://www.pro-football-reference.com/years/2019/index.htm The deeper question is why not use z-scores or percentiles like you said. In principle that's the better approach, but only if the data are fairly reliable for the sample size you have (32 teams in a year). There's something called the Fano factor which is just the variance divided by the mean and intuitively represents a "noise-to-signal" ratio. The larger that is the less reliable the data are (there's more "noise" in the data). Since 1978 the Fano factor is fairly small for passer rating while it's larger for TD's and especially large for passing yards, meaning that you need many more samples for TD's and passing yards before they're reliable (it makes sense that passer rating is more reliable because it combines 4 stats into one). So when faced with that I just chose the ratio of the means as the basis for adjustment (for TD's and passing yards), though I wouldn't complain if someone actually used z-scores here. The results are just "noisier" and less reliable even if it's conceptually the better approach.
6000 yards/16 games = 375 yards a game. 60 TD/16 Games = 3.75 TD per game. I do think those numbers may be unattainable for a couple reasons. These reasons assume the team is trying to win and not just help him reach these numbers. 1) Even if you have the best QB ever you arent just going to throw the ball 50+ times a game regularly....if for no other reason than to protect your QBs health an minimize hits on him. 2) If you are scoring points at that insane rate it's likely you wont be playing every snap every game. You'll wind up sitting a lot of 4th quarters unless your defense is just cheese. 3) If you're taking a lot of leads early, I'd imagine there would be a healthy dose of run plays to shorten the game. 4) If you are gaining so many yards, I'd think your HB would steal at least a few TD away in the red zone unless you're 100% dedicated to the pass. 5) Being human, even Marino would have 2-3 subpar games in his prime form, meaning the averages from his other games would need to be higher. I dont think it's impossible, but I do think it's unlikely. I will say that occasionally someone has come "close" to 60, but the average league leader in TD's is usually in the mid 30's
No doubt whatsoever in my mind. He did what he did back in the age when DBs could molest WRs. Nowadays they draw a flag for looking at a WR cross eyed.