as for attack rate, that′s the purpose of dual wielding to begin with, choose any rpg with dual wielding in it and you get the same use, a high rate of low damaging attacks, I doubt Skyrim be any different.
Which is sad, its always the same crap but for a few PnP systems.
You don t do less damage because you have 2 weapons.
2 weapon only give you an aportunity to attack a second time in detriment of defense but counting on the opponent will to parry both attacks or attack and parry...as history show us.
Usually due to the high stamina bleed of dual wielding combat, both weapons where light, rapiere, sabre, daggers, short swords.... its not at all that we dont see much pictures of dual wielder until rennaissance, lighter weapons, before that eficiency was very dubious.
Bit i can t deny its cool.