I went on a bit of a rant about this on IRC yesterday. While I agree a patch
series is appropriate for many new features and bug fixes I don't think it
should be required for keeping openstack-common in sync. Especially since we
don't merge tests from openstack-common which would help verify that the person
doing the merges doesn't mess up the order of the patchset. If we were to
include the tests from openstack-common in each project this could change my
mind.

If someone wants to split openstack-common changes into patchsets that might be
Okay in small numbers. If you are merging say 5-10 changes from openstack common
into all the various openstack projects that could translate into a rather large
number of reviews (25+) for things that have been already reviewed once. For me
using patchsets to keep openstack-common in sync just causes thrashing of
Jenkins, SmokeStack, etc. for things that have already been gated. Seems like an
awful waste of review/CI time. In my opinion patchsets are the way to go with
getting things into openstack-common... but not when syncing to projects.

Hopefully this situation is short lived however and we start using a proper
library sooner rather than later.