From the first episode, all of America knew: Sam is a total sweetheart. We felt for her when she was given one of the worst punishments in "Big Brother" history and had to spend her first week in the house as a robot (yes, a robot... see below).
Luckily though, Sam has risen up the totem pole by getting a BB Power App, surviving the first eviction, and becoming the 4th HOH (Head of Household), all while forming a bond with Tyler, aka the most powerful player in the house. The HOH is safe from eviction for the week, must nominate two houseguests for replacement, plays in the Veto competition, replaces nominees during the Veto ceremony if needed, and only places an eviction vote in the event of a tie.
Most players who become HOH tend to be willing to hear everyone out and are often persuaded by their allies when picking their nominations for eviction. Sam did no such thing. She came inside from the HOH competition and declared that she already knew who she was dominating. She wouldn't even tell Tyler, her closest ally.
Also unheard of in the "Big Brother" House, Sam announced that the HOH room would be her own private room and that no one could be in the room if she was not in there, needing Sam's permission to even be in the room.
At the nomination ceremony, Sam nominated Haleigh and Kaitlyn, noting the way they use their sexuality to stay ahead in the game by manipulating the men into keeping them safe. Immediately, Haleigh and Kaitlyn erupted in the Diary Room. Haleigh was embarrassed that her family saw what she was being nominated for, while Kaitlyn insisted that Sam's nomination speech was "the opposite of women supporting women."
The Internet had lots of opinions about Sam's strategies as HOH. Some think she did the right thing, and others believe she made huge social game mistakes as she knew her BB Power App will offer the evicted player the opportunity to reenter the house.
Personally, I think Sam is playing "Big Brother" the way it's meant to be played. As HOH, she earned herself the right to make the rules about the HOH room for Week 4. No one else was able to hang onto the wall for as long as she did; she gets a reward. Sam also made the right call about nominations. She did not take influence from any other player and chose to go after her honest targets. Most other players would've made the "easy" move by getting out a non-threat. Sam, on the other hand, picked her nominees because they rule the house in a way she doesn't: they flirt to get ahead, a tried and true BB strategy, and Sam's just not that kind of girl. She recognizes that if it came down to final two and Fessy, Brett, and/or Tyler made it to jury, they would most likely vote for the girls that flirted with them over the girl that was their friend.
Even though Sam chose to go after only female players, I don't think Kaitlyn made a fair assessment of the situation. Like I said, Sam focused on nominees that play a very different game than her, a game that's hard to compete with. Additionally, women are not mandated to support women that demean themselves to solely sexual objects to get ahead. Kaitlyn's actions in the house thus far have reflected poorly on women and our values, if she really wants to group us all into one category as her comment suggests.
So yes, Sam's moves are controversial. However, she is bringing back the sort of gameplay, the kind where you actually PLAY THE FREAKING GAME with winning in mind, that made "Big Brother" what it is in the first place.