I always try to meet all my clients! I will buy them dinner no problem! I feel that by becoming their friend first, their reception will be no problem!
Some people on this site hate that approach, but that's how genuine I am, and my clients love the way I treat them! =)
I have done one wedding in which I didnt get to meet the clients face to face, and I will admit, I struggled at the event! The bride and groom were susposed to do their first dance after the big introduction, but the dad grabbed the mic, and was ready to do the prayer, and speeches! I was like..I talked to your daughter, and they wanted to dance first! Anyways...they ended up doing their dance later...and they said it was ok! However, it was just a start of a chaotic night. The dance was susposed to start at 9pm..however no one cleaned up the tables until like 9:30-9:45.....
The dance was susposed to end at 12..I gave them and extra 25 minutes...the last song i played the bride went apecrap, and wouldnt even shake my hand at the end of the night! i know the guests had a great time...however the bride was very upset! I dont think it was the last song...I think it was an culmination of the rest of the night that snowballed, and her alcohol in her system was upset. I know I shouldnt worry about it..but it does bother me! The reason I mentioned it is because I think it would have helped to meet them in person to make sure all issues would be dealt with accordingly.
So back to multi-oping.....
I think bdays/anniversaries/school dances etc etc etc are ok! And I think weddings are ok if you have the dj there to really take in what needs to happen. Also make sure your dj is asking the questions and not you! Make the Dj take control. Dont be afraid to step in, and remind of some questions your dj may have missed!
I had a double booking back in last august, and I let my friend ask all the questions, only interjecting when an issue had to be addressed. This helped with his person skills, and it helped me see where he was at in his DJing world.
BTW....he kicked ass that night! I am very proud of him with that wedding! It turned out to be a tougher crowd for him that originally thought, and he shined through! So yea...just make sure you have a DJ who understands the DJ world. Very very important!