Hi, David!
Not to be argumentative

but some of this depends on how the LMS is storing your AP bookmark information when you turn off cookie bookmarking.
For example, for AICC, AP does not send bookmark info to the AICC LESSON_STATUS field where this bookmark data is normally stored. You folks use the AICC CORE_LESSON group and your bookmarks tend to be rather long when you do this, especially in courses with many, many slides. I'm not an AICC expert but I'm assuming the LMS needs to be able to successfully record CORE_LESSON data in its tables with the bookmark info you send.
In our Saba 3.5 SP1 LMS, this data gets stored in an AICC table for vendor info and the field that contains these bookmarks is only 255 characters long. Any bookmark longer than that gets truncated.
I'm looking at the table right now and I'm seeing a lot of Articulate bookmarks being truncated.
So, unless I'm daft on all this

, just turning off the AP bookmark cookie may or may not work for your learners in an LMS. Check your LMS data model.
All the best.
- Gerry