Here's some perspective for you, if you feel a season is going unpredictably and want to know what’s normal.
Knowing the accuracy of betting lines especially relates to all positions in fantasy, but especially D/ST, because correctly guessing winners is key to good prediction. Betting lines give an objective look (affecting all rankings, not just mine).
This below chart highlights the mid-season of 2021.
I could generate a plot of "%Upsets per week", but here I stick with my usual look at correlation. A higher correlation means that Vegas was good at guessing game scores; a negative correlation means there were more upsets than correct picks.
Normal correlation is between 0.25 - 0.55
Yes week 1 is usually least predictable... but predictability quickly corrects by week 2
Betting line predictability does not really improve over the season (as many people think).
The 2021 season was
manic in weeks 2-6...
but weeks 7-11 were depressive
and weeks 8, 9, 10, and 11 were significantly below normal.