Found this at one of my favorite sites, Preaching Peace, by Michael Hardin and Jeff Krantz:
"This [sermon time] is one of those moments when we might be most effective modeling for our congregations the behavior commended by Jesus to his disciples, giving our hearers something to imitate rather than speaking to them of their mission."
Yes! Truthfully, in fact, we are probably always most effective when we model instead of just preaching. The adage that actions speak louder than words is certainly one that holds true. In fact, isn't that why Jesus' message is so powerful? He did as well as taught.