Further, you have to remember that if you have split the DB, a C&R only affects the FE.
For FE C&R in a "split" situation, you would do better to just use the auto-uploader to get a fresh (and therefore, presumably saved in a C&R state) copy of the FE. That solution is more like a C&R on Open than on Close but gives you a decent result.
For a monolithic, non-shared DB, I would STILL be a bit hesitant. In that case I would make a copy first, then C&R the copy. If THAT appears to work, then replace the production copy with the freshly C&R'd copy and save the original as a backup.
If you have a split DB and kick everyone out of the BE, then the same rule would apply as for the monolithic (single-file) DB. Backup, then C&R the copy, then if it looks OK, do the replacements.