Why not simply do what most other games do/did and have a separate MP .exe ? That way you could simply hash check the exe and .ini files and it would leave single player gamers alone to mod to their hearts content?
What I think is the issue, is that the devs/publishers don't want the community creating mods before they can release the same thing as a $$$ making DLC ... Skyrim's "Hearthfire" is a perfect example, with all the "they just stole the idea from X mod, I'm not paying for that" is their any wonder their now wary of the Nexus and modders in general?
(although I'm always fond of the quote " you can't stop the signal" ... So eventually the modders will win)
This game has such a severe case of "Consolitis" it's almost crippled, but they know that because the kids with consoles can't use most mods, they have a sure fire cash cow they can milk ... If modders become too effective, it will eat into their profits, and that is something NO game company or publisher wants, or will allow until they've "milked" everything they can from us ...
I've really grown to respect Bethesda's approach (which admittedly seems to have been a learning process for them *coughhorsearmorcough*), with modding and DLC. Firstly, they provide mod tools early on, not "when we've finished milking it".
This means that because they know there are very talented and creative modders out there, they have to provide something worthwhile as DLC: I don't mind at all paying for big expansions full of new locations, adventures, new items and characters; even something lackluster like F3's Operation Anchorage was a worthy effort at doing something new that a mod couldn't/wouldn't do. Modders mean slapping a few reskinned outfits and guns together is a no-no... instead, we get stuff like Point Lookout, Shivering Isles and Dawnguard (note that the latter wasn't so greedy as to include "should've-been-in-the-game-but-ran-out-of-time" stuff like mounted combat, which was free in a patch as it should be).
50% of Fallout New Vegas was clearly "inspired" by great and popular Fallout 3 mods (from weapon modification to food/drink systems). Did that bother me? No! It meant that they learned and took on board what players wanted and tried to provide out of the box.
Even Hearthfire (which I haven't played, not being much into Skyrim as yet) seems like an inexpensive little expansion mainly for console players who CAN'T have mods like PC players can (and this is due to Microsoft/Sony/Nintendo/necessity more than any game dev). Can PC players do that with mods? Probably. But for a few bucks, it's available to console players too... or for PC gamers who just play "out of the box". And at least if they copied a mod idea, it wasn't in the game to begin with, which is the worst kind of DLC there is!
Games which are mod-unfriendly - especially ones with a mostly-PC fan base - won't last very long. That might mean a sequel sooner, but savvy gamers will remember (I certainly would!) being burned the first time around.
Keeping a separate exe for multiplayer and one for single player is a perfect solution. Nobody wants to play online with cheaters, but I'd honestly rather take that chance if it was that or be told I can't mod my game and play the way *I* want to.
Sadly, the entertainment industry as a whole is shaping more and more around "you don't own what you buy, and can only watch/play/listen the way WE want you to".
Any dev/company who says "no modding allowed... you have to play the game the way WE designed it, like it or not!" is just another side of that.
Edited by banjo_oz, 27 October 2012 - 12:18 PM.