I found that the problem was corrupt data in the core_config_data table. Some how there was a row saved with path “general” and value NULL. That caused the hwole general section to return empty when asked for config data. When that row was removed, all was fine again. This also caused a problem with creating new product attributes in admin.
Thanks! That was my issue as well—a corrupt core_config_data table.—and that same offending line. Luckily it was just in my dev environment; when I pulled the current one from production, everything operated as it should.