[snakes1100]

There really is no harm, but there is no need to repair a table that isnt broke/crashed.

If the tables have overhead, a simple optimize will do.

If you ran a repair & your still getting those emails, then yes the shared how could be the cause, as those can be created for numerous reasons as i said previously, some can be from large joins or large order by, which you can run into both in the case of vb.

Large user table & piss poor resource settings by the host on a over sold virtual server with hundreds of accounts on it.

It may be time for your site to get on a vps & yes, godaddy sucks pitas....