When you're not playing the long game, it's entirely different.

ONce playoffs start, I drop some depth for my own key RB handcuffs and load up on D/STs with good match ups against teams that no longer care so much about winning.

Grabbing a QB to sink your opponent is good strategy in the post season where you don't need lottery tickets for 5 weeks down the road.
In week 1, that's stupid.
In week 15 of the NFL season, it's brilliant.