The omnibus-ctl that backs opscode-analytics-ctl in all current versions of Analytics has a bug during the cleanse process.
It removes /opt/opscode-analytics/service, which is needed by the opscode-analytics-ctl reconfigure command.
Here is a process for successfully cleansing an Analytics installation. This will remove all the data and preserve the config under /root
Copy the configuration backup from /root/opscode-analytics-cleanse<DATE>) to /etc/opscode-analytics
mkdir -p /opt/opscode-analytics/service