the game of dominoes, where the notation is made by chalk on a table

Since when? It has always been scored with lovely little ivory pegs in a cribbage board when I've played it, so I guess I had assumed that was normal! Now, darts has always been traditionally scored with chalk marks, and a long line of marks would indicate the completion of scoring throws, so to beat your opponent by a long chalk makes an obvious visual sense...

but as Fisk says, just supposition really =)