Cluster access is primarily defined in data.yaml, but additional group membership changes need to be made in LDAP. Having two data sources to edit causes overhead and is error-prone wrt stale data.
One way to solve this is to make data.yaml the authoritative source and auto-generate LDIFs based on changes made to data.yaml. These could then be merged/applied during the puppet-merge step (as long as the change touches modules/admin/data/data.yaml)