In the small minyan in Jerusalem where I spent the high holy days of my childhood, as the shaliach tzibur of mussaf would rise to start his prayers, a hush of trepidation would go through the congregation. It is a trepidation that I imagine many daveners feel before mussaf, as the chazzan opens the service with one of the most raw and open prayers in the machzor: Hineni, heAni miMa'as... "Here I am, a person of impoverished acts..."