Thread: Danger of renaming an enum label?

I'd like to rename one of the labels of an enum in PostgreSQL 9.2 This
can easily be done by updating pg_enum, as described at
http://tech.valgog.com/2010/08/alter-enum-in-postgresql.html but I'd
like to understand: what is the danger of doing so? If, as the post
says, the data only references the OID and not the name then it should
be safe, even if the label is used, right? But in that case why is this
not a supported operation (via ALTER TYPE)?