Why don't you just play how you want to play and enjoy the game? Even if the particular build you choose isn't the absolute best in terms of damage does that mean it is no longer viable? I think not. It's ridiculous to begrudgingly play a build you don't enjoy just because it has a higher damage output, and equally ridiculous to refuse to play a build you enjoy because it is not the best available.
Because everybody keeps telling me that daggers aren't viable in open conflict, especially against opponents with shields, or dragons.
I'm not going to use magic and I'm not going to switch weapons, so if two daggers aren't capable of holding their own, then I'm just going to get killed over and over. However, if daggers do get a boost from armsman, and all of the power attack perks as well, then I should be fine - especially if I have a companion tanking for me. I just wish we knew conclusively whether or not those perks work with daggers, which is why this thread was made, but we still don't know for sure.