Reformed people often complain about the broad evangelical sub-culture. They complain about it for many reasons, one of which being the lack of accountability that seems to be a major feature of it. In many corners of evangelicalism, church membership is not really taken all that seriously. In my own personal experience as a young evangelical, I was very active in my local Evangelical Free church in Columbia, MO during my high school years, including being on a leadership team helping to oversee and teach the junior high youth of the church, and yet during all that time I was never a member of the church. Not being a member of the church puts one beyond the formal discipline and government of the church, which is an important part of God's instructions for the accountability and growth of Christians.
There often being lots of evangelical churches around, many evangelicals flit from one church to another whenever they tire of the preaching of their former church, run into difficult personal problems, etc. Evangelicals tend often to think about the church in a congregationalist sort of way, meaning that they see the church of Christ as made up of lots of independent congregations or groups of congregations that are not formally united to each other or accountable to each other. The church is a big conglomeration of independent entities that are united only in informal fellowship, prayer groups, worship services, listening to the same Christian music, etc. This makes it easy to avoid the rigors of church discipline as described in Matthew 18:15-20 and elsewhere in the Scriptures.
These sorts of tendencies are rightly decried by Reformed Christians as demolishing the accountability Christ has set up in his church between individual Christians and between churches. This is one of the great problems of congregationalism. According to Scripture, Christians are to be united and accountable to their leaders and to each other in formal church membership, and churches are to be united and accountable to each other in binding concentric circles of church courts (local congregations, regional gatherings of churches, national councils, general councils of the entire church, etc.) (See here and here for more on this.) Biblically, there is no such thing as a lone ranger Christian or a loan ranger church or group of churches.
However, what has struck me recently is how, while Reformed Christians rightly complain about these independent tendencies in evangelicalism, the Reformed world itself today is dominated by the same sort of independency. Most people in the Reformed world today see the Reformed church as consisting of a conglomeration of multiple independent Reformed denominations (OPC, RCUS, PCA, RPCNA, FCS, FPCS, FCC, RPCS, RPCUS, WPCUS, RPNA, APC, ARC, and I could go on and on) that usually recognize each other as legitimate Reformed churches and yet remain out of formal full communion or accountability with each other. Reformed churches generally tend to care about church membership and church discipline more than your average evangelical, and they tend to be presbyterian in structure up to a point, so there is probably greater accountability overall in Reformed circles than in broader evangelical circles. But there is a lot less than there should be. Reformed people regularly flit from Reformed denomination to Reformed denomination in order to find a better fit for what "works best for them," whether that means that they like the preaching better, there is less strict (or more strict) discipline, a favorite Reformed teacher teaches there, etc. Many Reformed people have developed a collection of favorite Reformed teachers who run the spectrum of Reformed denominations (evangelicals have their Max Lucados and their Kay Arthurs, and we Reformed have our R.C. Sprouls and our R.J. Rushdoonys, etc,.), and there is a tendency not to care all that much about the exact particulars of denominational affiliation. Churches and individuals disagree with each other on important matters of doctrine and practice, and yet there is no strong accountability for such things in the broader multi-denominational Reformed world.
Like broad evangelicals, we Reformed Christians have too much lost sight of the need for formal accountability across the spectrum of the church. When the OPC makes a determination in its General Assembly, we cannot simply treat this as applying to the OPC but something that can be safely ignored if we just move over to the PCA, and vice versa. As we Reformed Christians, professing (mostly) to be presbyterian, should know, Christians and churches are called by God to take seriously the worldwide unity of the catholic church, and to embrace the reality of accountability across the whole of the church. Denominational separation is not a convenient opportunity to treat the church of Christ as a buffet table with many doctrinal and practical options we get to choose from to suit our taste. It is nothing less than sinful schism, a rending of the Body of Christ, and the loss of the accountability Christ placed in his church for his own glory and our own good. We need to recover a fully biblical view of the unity and authority of the church, so that we stop emulating the very things we criticize in the broad evangelical movement.