That explanation was simple: Record your test in a way that the synchronization needed to keep an AJAX session coherent is done by recording a SYNC step in front of an action.
Here is the manual page that describes this process:
AJAX Synchronization Loop -- General Description.
Our experience is that this is 99% reliable. That extra 1% can be very annoying, however, and it usually happens when the AJAX page in question actually does not have a stable enough content to allow the synchronization to happen only on visible text. In those cases we have to dig a bit deeper and this usually results in having the playback synchronization pivot on some internal property that relates to the structure of the page.
That usually involves using the
Playback Synchronization on DOM Element command.
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