Tier-based drafting: what a real cliff looks like

"Draft by tiers, not by rank" might be the most repeated advice in fantasy football, and it's good advice with a hole in the middle: nobody tells you what a tier is. So drafters squint at a ranking list, draw lines wherever the names feel different, and call the gaps cliffs. Some of those lines are real. Most are vibes.

We had to make this precise to build a draft engine, because "reach if the tier is ending" is only usable advice if the machine can say what a tier ending looks like. Here's what survived contact with the math.

Two things people call tiers

First, rank buckets: tier 1 is the elite handful at a position, tier 5 is depth. Useful shorthand for talking about players, and our board shows these badges too. But a bucket boundary is drawn by a human and doesn't tell you anything about the size of the drop across it.

Second, value cliffs: a large gap in projected value between one player and the next at his position. This is the thing worth changing your draft behavior over, and it needs a definition with numbers in it.

The cliff test our engine runs

A drop after a player has to clear two bars at once before we'll flag it:

• It's large relative to the position's texture. The gap has to be well above the typical gap between adjacent players at that position (our threshold starts at 1.5 times the median gap). On a smooth board, every pick is slightly better than the next; that's not a cliff, that's a slope.
• It's large in absolute terms. The drop also has to be a meaningful share of the player's own value, around 15% in a single step. A statistically unusual gap between two late-round tight ends can be eight points; nobody should reach over eight points.

And one scoping rule: we only look for cliffs near the top of a position's draftable pool, roughly the first 18 players. Deep-bench gaps are noise wearing a trench coat.

Run your own tiers through that test and you'll find something humbling: most of the cliffs you've reached for weren't there. The gap between WR14 and WR15 in a typical year fails both bars. The gap after the last elite tight end usually passes both, which is why that particular reach keeps being right.

The better question: who's there when you're back?

A cliff tells you a drop exists. The draft-table question is sharper: compare the player in front of you not to the next guy at his position, but to the best player at that position likely to survive until your next pick. In our engine this is the single timing term in the whole score. If the surviving alternative is nearly as good, the cliff is decorative, wait. If the position empties before the snake returns, the drop is real for you specifically, and paying a small premium to beat it is correct.

Positional runs feed this too. Three or more picks at one position inside the last six selections, at double the position's normal share, means the room is draining a tier faster than any pre-draft math assumed. Our board flags runs as they form; at a live table, you're the one counting.

FAQ

How many tiers should I draw per position? Fewer than feels rigorous. If your tiers have two players each, you've drawn rankings with extra steps. Draw lines only where the drop would genuinely change your pick, which for most positions is three or four places.

Is reaching a full round for the last player in a tier ever right? If the cliff passes both bars and the survivability math says he's gone before your next pick, a round is sometimes fair. What you're paying is the difference between him and the post-cliff alternative; price the reach against that, not against ADP.

Do tiers matter more in some formats? They bite hardest where replacement level is far away: superflex QBs and thin TE years produce the most genuine cliffs. In guillotine leagues we deliberately halve the timing term, since eliminated rosters keep refilling the pool all season.