He cites Derrick as a prime example because the BOB twist did not effect Derrick in any way- there were double the noms and he was still never nominated.
The twist helped his game... And the 2 people that actually were willing to target Derrick were then thrown into a producer alliance. So he has a twist that discourages people to nominate him and a producer alliance w/ people that would nominate him. Like Rachel having duo twist helped her game and Shelly got screwed forced to pair up w/ Adam who is dead weight and her strength wasn't comps. You can't say Rachel wasn't affected by it so she's a very great player because she was positively affected by it.
And twists do ruin games. What is Jessie going to do in Coup De tat? Not letting Chima vote and him to be able to have time to talk to people he was screwed. Give him 10 minutes and let Chima vote and he stays. You can't just be prepared for everything.
A lot of people can get around twists but blatant favoritism can screw people playing well. This idea that people can always adapt but having something like that sucks and twists usually make the seasons worse. When you keep throwing twists in that blatantly save characters we won't ever get another Dr. Will, Dan, BB2 Nicole, etc that have charisma to pull off impressive moves because once someone is in danger that people like they don't have to work for it. It's like when Frank was on the block in danger you having him begging to cameras to give him a special power. Or Elissa asking for MVP(which turning BB into a complete numbers game was super fun /s).
He basically says the whole point of BB is to throw twists and mess with the HGs and it's not a game with straight/strict rules.
BB at its peak is when you have a great cast of people put them in a house and have them play this fucked up game. Because w/ interesting people fighting for this money you have people doing crazy things and fighting. It isn't a coincidence the best twists involve twist in casting not major gameplay change.
Also having a twist screw someone over sucks. If you hate them watching them have a downfall because of their own errors is way better than "well they just got screwed by production".