I'm not sure I see what you see in Example 16.8-1. A slur after the last note of a string to be repeated is not ever included in the result of a repeat mark. I think the confusion is exactly what the example is intended to illustrate. While the slur in question is not included in the repeat according to the rule, its presence in the original may "interfere with the clear perception of phrasing." Even though the repeat device does not technically include the slur, it does not erase it from the original. A reader who comes to the repeat device and goes back to re-read the repeated string will re-encounter that slur and want to connect it to the music that follows the repeat sign. Since there is doubt, the passage should be written out.
Example 16.8-5 reinforces the point. If single or double slurs are being used, the repeat device should not be employed, but sometimes bracket slurs may make the repeat sign usable. This distinction sometimes becomes very apparent in melismatic vocal music. See also Example 16.16-3.
Sometimes we transcribers are expected to follow rules that readers don't need to be aware of, if we do our jobs well. This may be one of those instances.
I think 16.9 should be revised to say "tie or single- or double-slur," and I've marked it to be brought up in the revising discussions.