One of the practical concerns about contemporary worship is having pastors who are competent to plan and lead it. Contemporary worship places far greater demands on pastors than traditional worship. In traditional services, the order, readings, introits and the like are all laid out. With the resources available, even many of the hymns are virtually predetermined. Contemporary worship is a new production, top to bottom each week. The pastor or worship planner has to spend a great deal of time in worship planning. Then, because it is different each week, it also must be rehearsed to have good execution. This requires more time. One has to be pretty committed to contemporary worship to put in that kind of time, especially with the time demands for sick calls, meetings, and the like.
The problem in the LCMS is that the young pastors, age 45 and younger have no interest in contemporary worship. Further, they see no value in it. There is no real world evidence that it actually increases growth. That was one of the stunners from the Klaas report from the mid 1990's. (Incredibly, the Klaas report, though their data showed no benefit to contemporary worship, still insisted that the best course of action was for every congregation to offer both traditional and contemporary services.) So the younger pastors, who see no benefit to it, will not invest the time in it. Most the guys my age and younger actually just refuse to do contemporary worship at all. So what will happen to those congregations that do contemporary worship when the current crop of pastors retire? Most will check out in the next ten years. Where will they get their pastors from? I can actually envision a time coming when we have a block of pastors sitting without calls at the same time as we have large numbers of congregations vacant. The pastors won't do contemporary worship and the congregations will only call pastors who are open to it.
We've already had one incident where a pastor told a congregation right up front that he didn't do contemporary worship and was removed from his call. In this shameful case, the pastor asked the congregation to tell him up front if his refusal to do contemporary worship would cause a problem. He only accepted the call after he was assured that it would not. After he was installed the elders "ordered" him to do contemporary worship. When he refused and pointed them to his earlier discussion with them, which I believe was in writing, they rescinded his call.
I fear we may have more such incidents in the future.