8691 net-routing-setup does a match for "current=enabled" against the ipv[46]-routing "persistent" field
net-routing-setup does a check to determine "Are we routing dynamically?", but the nawk prog prints field $2 (persistent=enabled|disabled) and tries to match "current=enabled".
2875 local zones should not enforce "smf_netstrategy==none" regardless of reality
Historical issue regarding ngz and netstrategy
7650 Update net-svc to work for an exclusive-IP, DHCP non-global zone
For a DHCP global zone, net-svc (svc:/network/service:default) creates/updates resolv.conf to incorporate DHCP DNSserv and DNSdmain parameter values and updates nsswitch.conf to ensure dns is set as an active database for hosts/ipnodes.
net-svc does nothing for an exclusive-IP, DHCP, non-global zone; but it could do easily the equivalent. Moreover, net-svc only tries once to fetch DNSserv and DNSdmain from dhcpagent (dhcpinfo), which generally works for a global zone. For fast-booting non-global zones, there needs to be a few seconds allowance.
8689 Update identity-node to work for an exclusive-IP, DHCP, non-global zone
For a DHCP global zone, identity-node (svc:/system/identity:node) will use DHCP Hostname if returned. As with 7650, identity-node does nothing for an exclusive-IP, DHCP, non-global zone; but it could do easily the equivalent. One particular difference is that the previously-existing, non-global zone fallback to uname -n after /etc/nodename must be preserved for DHCP-handling as well.
8690 Update net-routing-setup to work for an exclusive-IP, DHCP, non-global zone
For a DHCP global zone, net-routing-setup (svc:/network/routing-setup:default) will use DHCP Router if defined as a signal to disable routeadm/default-ipv4-routing. net-routing-setup does nothing for an exclusive-IP, DHCP, non-global zone; but it could do easily the same.
8587 svc:/network/routing/route:default usually is not needed nowadays
net-routing-setup uses defined "defrouters" as a signal to disable routing. Default, static routes from /etc/inet/static_routes should also be included in this signal. (net-routing-setup reads /etc/inet/static_routes as the last step in its handling, so this is not a major change to the script.)

Global zone

affirmed that DHCP Hostname was used if defined for DHCP address (as before)
affirmed that resolv.conf was created/revised and nsswitch.conf was revised for a DHCP address (as before)
affirmed that DHCP IPv4 address (with DHCP Router defined) resulted in disabled routeadm/default-ipv4-routing (as before)
affirmed that static IPv4 address with default, static route resulted in disabled routeadm/default-ipv4-routing (new)

Non-global zone

affirmed that first boot (no addresses) has routeadm/default-ipv4-routing enabled (as before)
after creating DHCP address and rebooting:

 1) affirmed that defined DHCP Router resulted in disabled routeadm/default-ipv4-routing (new)

 2) affirmed that DHCP Hostname was used if defined for DHCP address (new)

 3) affirmed that resolv.conf was created/revised and nsswitch.conf was revised (new)
For testing 8691: removed address and rebooted to see routeadm/default-ipv4-routing enabled. Added a debug statement to net-routing-setup to affirm the expected assignment: dynamic_routing="true".