If you like, we can start a new thread to troubleshoot this former issue of yours, because not even Apache 1.3 will match a leading slash from an htaccess file.
The value will indeed be “off”. This is confirmed by the documentation:
HTTPS: Will contain the text “on” if the connection is using SSL/TLS, or “off” otherwise.
As well as by the logs:
RewriteCond: input=‘off’ pattern=‘!on’ => matched