Thanks for the links, definitely gave me a little bit better perspective on what's going on there in integration.
tl;dr: Pretty tightly coupled. Server-authorative. Would tend to agree with the general assessment that mixing networking methods without some deep diving is likely to lead to oversights in security if that's what they meant. Otherwise would like to hear about it as an issue at a minimum.
I do see how "neatly" the Torque networking is written, it's definitely better than a lot of networking I've seen in other projects.
Details for the particular setup you're shooting for would be useful, but on a basic level, I'm not sure how extreme a security risk an uninitialized and unused networking layer would be.
The worry my buds expressed wasn't so much of exploiting the system as it is, but having the underlying and unused networking there, if we ever decided to offer a paid upgrade system to the game, would allow a way for people to figure out how to set up their own multiplayer system just as good or better without paying. Sure, that shouldn't happen based on the idea people would go for ease of use versus cost, but look at all the WoW private servers, the desire to avoid payment is there. I know the argument and idea is silly in an open source setup of a project's engine, but it's still completely viable, right?
If your security buds have specific points of concern a la security, those could probably be addressed, but if your stuff doesn't interact with the existing networking, I don't think it'd really matter much.
Again, very true that it's not an issue too much of immediate security, but allowing such a thing to exist untouched invites it to be used as an exploit in some form. If my train of thought makes sense.
Final note: I would give details in particular, however at this point with all the engine modifications and overall design preplanning I'm working on to see if what we want is possible within the realm of reason, I'd rather just see if in a generic sense what I'm asking is so.