Graham Hays of ESPN wrote an insightful article that compared the 47 times a RB has ran for 1,500 yards or more (since the advent of the 16 game schedule in 1978) and how they did the following season. Obviously the 6 who did it last season aren't compared since we don't know how they will do this season. He mentions 56 players but in his groups fails to mention 3, unless I just missed them somewhere
http://games.espn.go.com/content/ffl/20 ... id=1803938
To summarize, 40% of the time the back improved his numbers or 'held steady'. 1600 yards and 12 TDs for Lewis would likely fall into this category.
30% of the time there was a slight decline. Dickerson and Sanders 2000 yard years and their subsequent slumps are listed in this category.
30% of the time the following season was a bust a la Terrell Davis.
While you might not agree with his groupings, it is useful to look at the trends.
"One more set of numbers to confuse things just that much more: There are 30 running backs who rushed for between 1,500 and 1,700 yards and 17 running backs who rushed for more than 1,700 yards. Here are their average yards gained for each group the next season.
1,500-1,700 yards: 1,261 yards
1,701-plus yards: 1,205 yards"
Monster (1700+ yards) years are something special. A number of factors have to come together to produce one, and expecting a repeat performance is asking for disappointment.
Of course that's only looking at rushing yards and obviously touchdowns play a big role in fantasy scoring as well.