I don't really like the idea of making an inflammatory thread just for the sake of discussing one boss from Dark Souls. I'll get a bunch of people's attention but it's usually filled with stupid one comment drive-by posts.
Well, for me maybe the first time you fight two bosses that actually battle as a team and dont take turns to give your room or just have phases at all to give a breath is fight or get killed. O&S battle is about testing how much do you dominated the basic features of the game, your surroundings, your gear and weapons knowledge are in play this time.
You can get destroyed if you dont understand the basis of the room and how to get them separated, some players can get it at first try by actually knowing the blacksmith mechanics, using guides or getting summons, others dont, the song actually gives you the vibes this not not your usuall boss battle but something menacing and rewarding and when you defeated one you have the impression of "Phew, one down now lets take the other g....holy shit" vibe, its an unique feeling I never felt before in a long time.
You can say Smoug have predictable moves but his moves are very a masquerade and can hurt you, bad, if you dont take him seriously while ornstein is the classic agile boss that wont let you hit his bro and have moves that can break your guard if he sees your guarding too much, giving smoug time to charge his moves and seek for a window to hit you it but if you use ornstein as your shield, Smoug won try to hit you and look for a entrance in your sides or ornstein will move to let smoug hit you.
After the battle the feeling of reward is huge ingame, you can finally take a break and the game stops for you to understand what to do now, if you take your time of course.
But returning to your issue the battle have no cheap mechanics compared to DS2 bosses, a perfect example is the throne battle for the O&S esque battle returns.
This time the enviroment is plain and simple, with some holes on the edges, the duo just charges at you no matter what happens even if they have to pass each other hit boxes to hit you and no window to attack because the other one just instant jump and hit you in a inrealistic angle so you are just guarding yourself the entire battle praying for a single blow with out being hit by the duo which happens very often.
They dont have stamina, not stun animation, not coordination or teamwork they are just there moving so fast they can clash each other and didnt care but when you hit them both attack you and hurts you back you dont have time to do shit against them.
What to do? overgear yourself and kill them, thats all,just roll and maul them faster than them to you, there is no strategy in most of the bosses. You kill them and that all, souls gained.
The gank squad, where to begin with those guys.
The three of them have infinite stamina.
Havel have instant frames to hit and pretty much destroys your shield guard and energy
The small guy have invincible frames and instant frames to avoid to be backstabbed
The archer have instant swap weapons and can use the great bow without penalty at all
Is like seeing a moded agression mod for NPCs acting like a boss battle.
But if you like the bosses in DS2 its fine.