I sometimes heat things to temperature in the microwave, which cuts down on oven time and makes it easier to get everything to the table at the right time. For example, tomorrow I will nuke the vegetable casserole until it is as hot as I want to serve it. Then, when the turkey comes out, it can go into the oven with the rolls on a higher temp so the top crisps along with the rolls, and everything comes out the right texture as well. I often do it with baked potatoes. Nuke them until almost cooked, then put in a very hot oven for a few minutes until the skin crisps. Luckily, as everyone else says, nothing you are cooking is really that temp/time sensitive. I think that timing all the dishes in a meal can be the hardest thing when it comes to cooking for a large group. Using a microwave oven to pre-heat the food, or re-heat something when it all goes south can be a lifesaver.