Well if we look at this purley from an in game perspective, then there inclusion, like most have said, was very little indeed. I think this was mainly because the game still wanted to capture the idea of Link being a "lone wolf", maybe if they had a bigger influence it would have impacted the idea of Link as a whole.
However, they did have some impact. Look at all of the characters in the game... Now I doubt many people could name that many characters that genuinely helped Link on his journey. This group certainly did, but they're influence was toned down somewhat to still keep that feeling of Link being this lone hero.
Plus regarding them being a "resistance", well they are if you think about it. They are resisting against the evil in the world, now why didn't they get far? Because they see evil as the random monsters scattered across Hyrule and these random events that seem to occur, but they remain oblivious. They are accomplished people, but they don't have the required knowledge to truly tackle what's out there. Link only knows because he befriends Midna and as well as meeting helpful spiritual figures along the way -- such his role as the hero is. So their role was to take a back seat and try and find out what indeed is happening -- this explains why they spent their time planning and investigating.
So I do feel they did help somewhat, they were certainly better than those cowardly Hylian Soldiers who ran off at the sight if a mentioning of a monster. But more of a backseat figure, yes.