rule 17

[Jean-Luc Dellis]

that is, when the overlap occurs across a medium boat Rule 17 does not apply.
but between the three boats only 11 and 16 are in effect ?

No, 17 still applies between the 2 external boats but 17 is not broken while the middle boat stays on her proper course. So the boat may luff if it is her proper course to keep clear from a third boat.

[euphoria]

that is, when the overlap occurs across a medium boat Rule 17 does not apply.
but between the three boats only 11 and 16 are in effect ?
and rule 17 applies again if the leeward one makes gube .
I did understand correctly ?

If I understand you correct, then you are not correct

For 17 it does not matter how the overlap is:
- Either directly overlapped between two boats.
- Or indirectly overlapped with a boat in the middle overlapping both.

The only thing that matters is how the overlap was established:
- Leeward overlap from clear astern, 17 applies
- Leeward overlap from clear ahead, 17 does not apply
- Leeward overlap instant (from tacking), 17 does not apply

Harald