Bruce,
Yes, REINDEX will compact a CDX without disrupting the DBC. REINDEX still will not recover a CDX from all possible corruption that can affect it so tools like gendbcx and Stonefield are useful.
>Oh, no :) Just after the deleted index controversy, do I now need to reassess the old prescribed DELETE TAG ALL and create fresh indexes periodically method? Are you saying that REINDEX has become useful? :)