The Small Road (小路) is the second derived road, and if you already understand Big Eye Boy there is exactly one new thing to learn: it looks two columns back instead of one.
That is the whole difference. Same two questions, same colors, same grid, same bending. Change the lookback distance and Big Eye Boy becomes the Small Road. What that one change produces, though, is the case that confuses people most — so it is worth walking properly.
What the lookback actually means
Each derived road compares the Big Road against an earlier column. How much earlier is the only thing that separates them:
| Road | Looks back | Starts at | Symbol |
|---|---|---|---|
| Big Eye Boy | 1 column | Col 2 Row 2, or Col 3 Row 1 | Hollow circle |
| Small Road — this page | 2 columns | Col 3 Row 2, or Col 4 Row 1 | Filled circle |
| Cockroach Pig | 3 columns | Col 4 Row 2, or Col 5 Row 1 | Slash |
Notice that the Small Road skips the column immediately to its left. It is not looking at the most recent comparable column; it is deliberately looking past it. That is what gives it a longer memory than Big Eye Boy and makes it react more slowly to a shoe that has just changed character.
When the Small Road starts
At Column 3, Row 2, or Column 4, Row 1 if Column 3 never gets a second entry — whichever arrives first. One column later than Big Eye Boy, because it needs one more column of history before it has anything to compare against.
On a real board this is visible: the Small Road is always a little shorter than Big Eye Boy, and Cockroach Pig shorter still.
The two questions (unchanged)
Question A — the Big Road started a new column
Compare the depth of the column that just finished against the depth of the column two further back. Same depth is red, different is blue.
Question B — the Big Road moved down a column
Look at the column two to the left, at the row you just landed on and the row above it. Both filled or both empty is red; one of each is blue.
A shoe that shows it clearly
BBPPBBBBBPPBPBBPPBBPPB
Twenty-two hands. Every diagram below is drawn by the same road engine that powers our free Road Decoder.
The first four marks
The Small Road’s first mark appears as the Big Road goes down to Column 3, Row 2. Its reference column is two back: Column 1, which is 2 deep.
- Red. Column 3, Row 2. Column 1 is 2 deep, so Rows 1 and 2 there are both filled. Same answer twice.
- Blue. Column 3, Row 3. Column 1 stops at Row 2, so Row 3 is empty while Row 2 is filled. The answer changed — this is the transition point.
- Red. Column 3, Row 4. Now Column 1 is entirely above us: Rows 3 and 4 there are both empty. Same answer twice.
- Red. Column 3, Row 5. Same again — Rows 4 and 5 of Column 1 are both empty.
Marks 3 and 4 are the whole lesson. The Big Road is in the middle of a five-hand Banker streak, the reference column ran out two rows ago, and the Small Road turns red — twice. Nothing is malfunctioning. Once you pass the bottom of the reference column, every further step down is “empty, empty”, and empty-empty is consistent.
Then it changes: the fifth mark is blue, because the Big Road opened a new column and Question A compares Column 3’s depth of 5 against Column 1’s depth of 2. Different, so blue.
Same shoe, two different pictures
Run Big Eye Boy on this identical shoe and you get 19 entries against the Small Road’s 17, in a visibly different pattern. Nothing about the hands changed — only the distance each road is measuring from.
This is the most useful thing to understand about the derived roads as a set. When players say the roads “agree” or “diverge”, that is all they mean: three lookback distances, applied to one finished history, sometimes producing the same answer and sometimes not.
Why filled circles?
Purely so you can tell the three roads apart at a glance on a crowded display. Big Eye Boy uses hollow circles, the Small Road filled circles, Cockroach Pig diagonal slashes. The shape identifies the road; the color carries the meaning.
What the Small Road cannot do
The Small Road is arithmetic performed on columns that already exist. It cannot see a single card that has not been dealt, and it adds no information to the Big Road it was calculated from — it re-expresses it. A long red run means the shoe has been repeating a shape, in the past tense. The next hand does not know about it.
Finish the set
With the lookback idea in hand, Cockroach Pig takes about two minutes: same two questions again, three columns back.
Then practise. Enter hands one at a time in our Road Decoder — free, no account — and call each color before it appears. Watch what happens to the Small Road during a long streak in particular; that is where the empty-empty case lives.