Yet it is a point which I believe is fallacious. It is a false argument.
That is not a false argument no matter what you may wish to believe. Development resources are limited. And it would take considerable resources to implement it properly. The resources it would take to develop it properly would distract from the single player game, at all times, unless Bethesda massively increases it's development budgets. This is not an opinion, it is basic fact.
Besides that: why do you think there are no games that combine the scope and extensiveness of the TES single player with a co-op that is equally entertaining? It really just isn't as simple as you seem to want it to be.
The absence of co-op does not add anything to The Elder Scrolls. It merely subtracts. It may not be a detraction to the minds of all, but it is a shortcoming in the minds of enough that it can legitimately be considered a shortcoming. For many, its absence leaves in the category of good a game that would otherwise be astoundingly great and perhaps beyond all current comparison[/size]. [/b]
I can understand that sentiment. But it is just your opinion, not fact.
I hear very few people complain that they think less of TES because there is no co-op. What I do hear is that there are many people hoping to see Bethesda do a MMO somewhere in the future.
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None of these things are certain. The developers would need to make a list of things they wanted to accomplish prior to development, and put co-op on that list. I would all but guaruntee that, given time and effort, they could CERTAINLY achieve all of their intended game goals, giving exactly the game that would have been released as a single player game. .. but with a heavenly co-op local option. It can be done. I think we all know that it can be done, if only the will exists to do it.
It will consume man-hours. Man-hours which could have been spent elsewhere.
Unless Bethesda increase the available man-hours (meaning increasing the development budget and either hiring more staff or stretching development time) those man-hours will have to be taken from elsewhere. So yes, then it would come at a cost for the single player game. There simply is no sense in denying that.
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You may keep good hopes that Bethesda (and the larger Zenimax group) will stay on the current trend of growth. If they maintain that growth then thee development budgets could very well soar high enough for Beth to be able to incorporate co-op (etc) in their single player franchises, without there being a detrimental effect on the single player game. So there is hope if you wish to have co-op, but for the time being it's still just too soon. Also, the economical climate just isn't right at the moment for Bethesda to take risks by overstretching it's development resources.