QOS best practice (Janism document)

Hi all.
I have read the Janism pdf (http://mum.mikrotik.com/presentations/US08/janism.pdf) about best practice in QoS in large scale networks.
This very interesting document keep in my mind some questions:

  1. is it possible to encapsulate a traffic prioritization inside a pcq ? i.e. for each user of a given pcq queue, can I prioritize the traffic ?
  2. if I set max-limit and burst information int the pcq type queue, it override the secret rate limit profile ?
  3. it is not very clear the PCQ Adjustments where janus calculate pcq_total limit for 340 basic class clients with pcq_limit=40. Janism indicate 20340. Could it be 40340 ?
  4. wath is the effect of a smaller pcq_limit ?

thanks of all.
Marie