How many times to I have to say this? Who's listening? Anyone?
Don't preach another sermon at the Table before Communion. We've already heard one sermon; and it if it was a Presbyterian sermon, it was probably already much too long. Why do we need to hear another sermonette before the Supper? Enough talking. We don't need another extended explanation or invitation to the Table before the Lord's Supper. Just do the Supper as Jesus commanded.
Our tradition is so very screwy on this point. We feel like we have to "fence" the Table long and hard in order for the Supper to be effective, so that people will take it seriously enough. Even if we grant the need to take the Supper seriously, what makes us think that talking about it for 15 minutes before we pass out the food will actually make a difference? Presbyterians don't seem to be able to appreciate ritual unless every step is "explained" in the liturgy.
Besides, the Table is not all about us turning in on ourselves or even our individual devotional experience with the Lord. It's a social event, a ritual meal with other people!
It's no surprise to me that most Presbyterian and Reformed churches don't practice weekly communion. Who would want to endure such a protracted call to "serious" self-reflection and "genuine," "honest," "true," "real," "internal" appreciation of the Table every dang week? Not me.
Remember, I've argued against this kind of thing at length here. Perhaps I should serialize my talk at this year's PCA General Assembly and post it here on my blog.