I have been studying dysfunctional churches for over 20 years, since I was asked to leave a church with a similar structure. All dysfunctional churches to a less or greater degree have what I call the cultic system. All problems start with the leadership. The pastor sets the tone and then the underlings impliment that tone or can inhance the tone. Since I have only been to GCC a few times, I can not know for sure who is driving the culture, but the pastor is responsible to correct it, if it is unbiblical.
What I do know is the consistent attitudes and "fruit' of the many people over the years that attend there. I personally suffered as a pastor in a church where the elders had read MacArthur's false teaching on Lordship Salvation called "The Gospel according to Jesus" This teaching promotes modern day Phariseism where the people no longer recognize their fallen nature and sins and rationalize their destructive actions as holy. These MacArthurphiles would rationalize lying, backbitting, destructive gosip, and harsh critisism of others and call it a holy attempt to protect God's kingdom.
My experience with people from GCC is that they are encouraged either directly or more often the case subliminally to be haughty and judgemental of people outside the fellowship by judging their actions and declairing them unsaved. To them your only hope is to be rebaptized in MacArthur's church while declairing you have conquered all sinful thoughts as well as deeds since you made Jesus Lord. Of course at the same time they lose all critical thinking about the people who lead them, especially MacArthur and treat him and the pastors as if they have no sin. If MacArthur is still a sinner, (yes Spiritual Pride at least) and the congregation discovered that truth the entire culture would collapes. The last thing you will see at GCC is people sharing their faults with one another - this would prove them an unbeliever at GCC.
At GCC there is a culture of worshiping John MacArthurs teaching without using any critical thinking. Just this last Sunday night I was there for a baptism. MacArthur in front of 4000 people redefined the word Faith to mean Good Works instead of trusting belief. Faith became the substitute for the power of the Holy Spirit to change the human condition. Grace is redefined as surrendered Lordship to Christ instead of unmerrited favor. The attonement is limited to the elect and salvation and hell are predestined by a malicious God who has predetermined who will not recieve that grace.
Fatalism and spiritual striving to prove yourself worthy of being called the elect is the culture at that church. So to admit that you struggle with sinful thoughts and actions like Paul did in Romans Chapture 7 is an admission of not being saved. The culture is very much like the Stepford Wives. Everyone must put on a personna of perfection and niceness (unless we are trashing some other church or unbeliever). One of the fruits of the cultic system is that eventually every one must act alike, talk alike, dress alike and think alike in order to be percieved as one of the in crowd. Everyone will take on the personallity of the leader which is seen as holy. So the culture is one of dishonesty. Lie to myself, God and others about my sinful thoughts and habits so I will not be judged as and outsider or as unsaved. Rationalize all my dysfunctional behavior and pride as part of the personality of a true believer. Everyone is pretending to be completely victorious over sin.
Here are some good articles on the error of Lordship Salvation.
take care - pastrpath