How much time is needed for formal group shots on the wedding day?

How much time is needed for formal group shots on the wedding day?

I don't have any traditions or formalities when it comes to photography, especially wedding photography. As for formal group shots on the wedding day, I only arrange those which are requested. Before the day, I contact my couples and ask them to think about what group shots they really want, if I'm going to start directing and moving people around, and more importantly keeping people from the bar! Then I want to make sure it's something my couples are actually interested in and want.

The morning of a wedding day, bridal prep

 Emma // Bridal prep at The Fennes, Essex

Emma // Bridal prep at The Fennes, Essex

I usually start my wedding day coverage with bridal prep; it's a lovely part of the day which only a few people get to enjoy at each wedding. Me being one of the lucky ones. 
I enjoy this part of the morning because it's mostly very relaxed, I get to meet those closet to the bride, they get to know me a little, and they also get used to having me hanging around.
I love hearing the stories. I might get lucky and have the bride share an embarrassing tale regarding the groom, or learn about some odd quirks, or surprises planned for the day. Something I'd otherwise have missed or not known about if I hadn't been there.
If this isn't for you then not to worry, not all of my brides want photos of the bridal prep time, which I'm totally fine with. It's your day so do what makes you happy.

Ninja mode

 Vickie and Lee struggle with the rings at Pontlands Park, Chelmsford.

Vickie and Lee struggle with the rings at Pontlands Park, Chelmsford.

When it's time to get married the only direction I give my couples is to ignore me during the ceremony. I don't care if I faint, fall, or spontaneously combust, pretend I'm not there. Please give your attention to each other, the officials on the day and enjoy the moment.
During the ceremony, I do my best to be discreet and go unnoticed. To do this I find out about any photographic restrictions, I avoid using flash, and I engage full ninja mode. I must do pretty well, after the ceremony at a recent wedding one of the registrars asked who the official photographer was  "It's me, the guy with the camera standing next to you" ;).
Restrictions will vary from registrar to registrar; everyone has different views, and that's cool. Sometimes I meet someone very strict, and I'm only allowed to take photos at certain moments, but that's never been an issue for me. 
Introducing myself before the ceremony, to say hello, and to find out about any restrictions goes a long way. When I meet a strict registrar I charm them as quickly as I can ;) and ask a few questions. I usually find they may have had a bad experience with a previous photographer. Once I assure them I'm not going to use flash or be a nuisance everything usually's okay, and they forget I'm there.