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10.36 specifies enabling LLQ for exactly one voip call;

Class VOIP
  priority 27

-This makes sense, but it polices the entire VOIP class to 27kbps.
The next task requirement specifies, Additional VOIP calls should be allowed only if the link is not congested, but they should not be prioritized.

-Class VOIP should be policing the entire class!  Once those 27kbps are gone, there shouldn't be any left for any other traffic that matches class VOIP.  How is it possible that additional voice traffic is allowed?  I'm fearing I have a severe fundemental issue.

Does the policer only kick in in times of congestion, but the packets are always prioritized?

policy-map R4_TO_R5
 class WWW
  set precedence 2
  bandwidth remaining percent 33
 class VOIP
  set dscp ef
  priority 27
 class ICMP
   drop
 class VLAN146
  set precedence 1
  bandwidth remaining percent 33
 class class-default
  fair-queue
  queue-limit 32

Some self discovery,

LLQ does police the queue but the word "police" is probably inappropriate - it limits the queue size when it is congested.  I was misunderstanding the technology, so the solution is fine (Aside for the really annoying qos math!)

LLQ traffic is policed ONLY if there is a congestion (more voip calls cannot be granted required prioritized bandwidth if other classes are granted their portions of minimum bandwidth too and over all interface bandwidth is limited)

If there is NO congestion then more than 27kbps is allowed via LLQ class but this time it's not prioritized. This is what solutions guide says (perhaps updated now).

Tom