Questions regarding WSC round 5 - Arrows, Lines and Circles

[Feadoor]

In general: if instructions don't forbid something, it is allowed.

I understand. But the instructions for 5.2 and 5.4 on the same page contain the sentences "Digits may repeat on arrows" and "Digits may repeat on strands" so the omission in 5.3 is striking.

While your general point is well-meant, I hope it doesn't discourage people from asking similar questions because it can be difficult to tell the difference between something that was left out of the IB because you didn't deem it important and something that was left out by error.