But there is another problem, one having to do not with substance but with logistics, that is more typical of praise band services than it is of traditional services. In my experience the service that utilizes a praise band relies so heavily on the band that were the band not there, there would be very little service left. There would be a few prayers and a sermon, but without the band there to lead (perform?) lengthy musical medleys and interludes, there would not be much else. I think this is a problem. No liturgy should stand or fall on the presence (or lack thereof) of any one musician or musical ensemble, and the congregation should not come expecting to hear a certain soundtrack. And I think in most traditional settings such is the case. The focus is not on who is sitting on the organ bench, or which cantor is leading the psalm, or which choir is assisting with the liturgy and hymns, but rather on Word and Sacrament. But in a service that takes its identity from the presence of a praise band, what happens when that group is not there? Does it all fall apart? Is the thing that remains, or that which is substituted, so foreign to those assembled that they don't know what to do or how to participate? Do they feel as though they have been deprived? If so, that is a problem.
To be fair, I think it is possible for the same pitfall to happen in traditional worship. If worship is no longer worship because it is not led by a pipe organ or because a certain preacher is not in the pulpit, that is a problem, too.