[LAU] Sync and digital audio transport

[Len Ovens]

Working my way through the AES3 variants (AES3, 10, 11, 47) and came
across this page:
http://www.glensound.co.uk/uat/pdf/atmaes47/atmaes47is.pdf

It is about using AES47 as a method of sending AES3 streams over net.
(simplified definition) Anyway this company make equipment for
sending/receiving audio streams to/from remote sites. At the bottom there
is this statement:

------------------8<-----------------
Inevitably sites are not always locked together. To cope with this our
AES47 equipment incorporates a clever algorithm that is capable of
realising that two clocks are not locked
together and then as necessary to prevent audible jitter the equipment
will drop or repeat samples during periods of silence in the audio or
if not available during periods of consistent
similar frequency and level.
---------------8<--------------------

Is this method of sync common in the professional world? How does it
compare to resampling when the frequencies are very close?

-- 
Len Ovens
www.OvenWerks.net