I (as others have stated) would worry about the car being in someone else's hands. I think that is more natural than the other way around. I have taught others how to drive my A. I can usually judge whether a person is going to be able to drive it or have difficulty. If I suspect difficulty, I keep them in first gear and only go around the block or down the street.
But, with the above being said, when my A is used for such an event as a wedding (example only, could be other event); I am the driver, no ifs-ands-or-buts. I am not so much worried about how the groom would handle things, but more worried about others being in harm’s way. As said in a previous post; the groom and bride are going to be thinking about their wedding, as well as all those invited. You, on the other hand, will be focused on the task at hand.
My pre-driving meeting with the prospective couple is:
1. I drive the car, period.
2. Warn them about oil and grease (doesn’t look good on a white dress or tux). Come up with a plan to prevent such a thing happening. When they are aware of this; they will be helpful in preventing any thing being soiled too.
3. Have them sit and ride in the car prior to the important day, so they know what to expect.
4. Drive the exact route they want; to make sure it is safe for you, the car, and them. Also, time the route so you know when to leave (I had to drive from one town to the next in one case).
5. No matter what the distance; have them provide a backup vehicle (I have every confidence in my Model A…….BUT!
6. And last; tell them inclement weather could cancel the whole drive. That you are not responsible for the weather, and that you have the final say if you will drive in it or not (another good reason for the backup vehicle).
I have never had a couple refuse my requests. By properly explaining each task (and using my best smile and tone); they can easily see this will be a special event for them.
Note-I also agree that the couple do the asking for the use of your Model A. When I am asked by anyone else (including immediate family or future in-laws); I state I will only honor said request from the couple.