As much as I hate to admit it, trying to include duplicates in my highlander decks or minions in my spell decks always resulted in a slightly lower win rate and a significantly lower consistency. But it can certainly be a lot more fun, and the surprise factor will definitely help you win some games and mitigate the lost games where your gameplan was disrupted because you didn't draw your duplicate/minion.
If you play a fully active Font of Power on turn 1, nobody is going to expect that you actually have Yogg or a Aegwynn in your hand.
If you play a Wildfire on turn 2 and Kazakus on turn 4, nobody is going to expect you have another Wildfire in the deck. There are exceptions to this, like Dead Man's Hand, even when played in highlander decks, I always assume there's another one.
You can take advantage of details like this.
To answer your question, can you win consistently enough and climb ladder with suboptimal decks ? Yes. Can you climb faster than optimal decks ? Probably not unless you're a god at this game.
Did you manage consistent wins even if you included a minion here and there or a duplicate? How far did you go?
As much as I hate to admit it, trying to include duplicates in my highlander decks or minions in my spell decks always resulted in a slightly lower win rate and a significantly lower consistency. But it can certainly be a lot more fun, and the surprise factor will definitely help you win some games and mitigate the lost games where your gameplan was disrupted because you didn't draw your duplicate/minion.
If you play a fully active Font of Power on turn 1, nobody is going to expect that you actually have Yogg or a Aegwynn in your hand.
If you play a Wildfire on turn 2 and Kazakus on turn 4, nobody is going to expect you have another Wildfire in the deck. There are exceptions to this, like Dead Man's Hand, even when played in highlander decks, I always assume there's another one.
You can take advantage of details like this.
To answer your question, can you win consistently enough and climb ladder with suboptimal decks ? Yes. Can you climb faster than optimal decks ? Probably not unless you're a god at this game.