>>> The group home page blurb has been fixed...
In retrospect I should have suggested this in my original post, but anyway, my suggestion is to change the blurb wording on MF groups from "Posts to this group that start a new topic require approval from the moderators" to something technically-correct but a bit more vague and less explicit, to possibly discourage (more) users from hijacking threads.
For example "New topic posts require approval from the moderators", same meaning as above, technically correct but maybe not as clear to the average user, more than likely they'll either miss the "new" part, or interpret it to mean ALL posts.
Or even have it be the same as shown currently for a moderated group, "Posts to this group require approval from the moderators", which itself is technically-correct for a moderated group but somewhat vague/less explicit to the average user, as it doesn't specify ALL posts, so therefore it could technically apply to both mod types. Or alternatively, maybe set the MF blurb to the current less-explicit moderated group blurb, and change the moderated group blurb to be the same but explicit, i.e. add also "All" to the beginning.
It wouldn't stop the die-hard savvy users from doing it (in which case particular member moderation will take care of that), but it may prevent the average not-as-savvy user from putting 2+2 together and starting hijacking threads.
Doing so may also allay fears of the MF setting encouraging hijacking overall, and encourage more folks to use it, as IMO it's a very good compromise between fully-moderated and wide-open, i.e. least-workload moderation and message free-flow, especially for support/technical groups; moderating just the opening topic gives you all the moderation advantages moderated groups have (keeping the group focused/OnTopic/weeding out, editing, categorizing/cataloging/organizing, etc), plus all the unmoderation advantages as well, it greatly reduces moderator time & workload by allowing the subsequent conversation to flow freely, and as a bonus, it benefits online users with a live forum message flow.