Several thing stop Pinsir, one of them being the most prevalent thing in the game in rocks. Skarmory laughs at anything Pinsir even thinks of doing. both of which are extremely common. Don't get me wrong, I'm not saying Pinsir isn't a threat, but it's no where near as broken as BP chains are. . .
When I said working as one, I didn't mean one team, I meant one Pokemon. . . It's essentially one HUGE Pokemon setting up until it feels it's time to start dealing damage. Pinsir can be phazed out, much like most set up sweepers. Good luck doing that with a competent player using a BP chain.
The thing is. . . People have began to prepare for it. . . Yet, BP and dEnIsSsS remain at least in the top two positions in the ladder (Not that great in your opinion, that's cute, you must be the greatest player ever). The thing is, if the person facing the BP chain makes one wrong move, it can lose them the game regardless of how "prepared" their team is, it's as simple as that. As I stated in my first comment on this thread, if you don't think BP chains are broken and uncompetitive, then you're one of two things, ignorant to what a COMPETITIVE meta game should look like, or biased.
If you don't see how BP chains are broken, then I'm not sure where you've been the last few months.