So Kematu, who is the antagonist in this questline maintains. And that is the rub. He IS the antagonist, of that there is no doubt. Saadia alone is no match for the playerborn while Kematu and his men are a stiff challenge. Even if he IS legit as he claims it still takes a step of faith to take him at his word. He IS very convincing, I've talked with him a couple of times before and concede that fact.
Sometimes I wonder; Is it high genius on Beth's part to make this quest, the CW and the Paarthurnax vs Blades as examples so ambiguous that the members of this forum can heatedly debate the points on both sides at length or just an example of shoddy writing as many proclaim?
The fact though is THIS, we are given such conflicting information at times that either side you wish to take can legitimately be argued for and these types of threads are an example of just HOW vehemetly many people approach these quests, staking a claim for their point of view and going to battle on the forums to support their stand.
This is one reason I enjoy the game so much and overlook the bugs which many have had and the shallow guilds. Skyrim is unarguably a galvanizing game whether you hate or love it and it demands you make a choices and take a stand. This alone makes it a worthwhile addition tio anyone's game repertoire IMO not to mention the combat, dungeons and memorable NPC's.