3 times character a, 3 times character b, 2 tmes character c of one clan will always give you the bonus.
However , should you have 4 times character A in one duel, you will not get a bonus on any card. The bonus is given for at least two (or more) different characters of the same clan.
Not exactly. Clan bonus will ONLY BE ACTIVATED when at least two DIFFERENT cards from the SAME clan appear in your opening hand. Hope that helps.