Scott, to your questions:
If you want to be the uber-Philmont-minimalist, then you'd dump about 1/2 the packaging to save about 2 ounces per meal for 12, not worth the effort for most I'd imagine. Where you can save a little more weight is to dump what you don't want/won't eat (ie "Gorp").
I don't think the bags are vacuum packed, but they are freeze dried / rehydrate meals, they are in plastic bags, not zip lock. You can get rid of the packaging and other trash when you get to the next staffed camp.
47 lbs is probably about average. We saw 2 trekkers in 2006 that were very proud (on day 1) of their 80 and 84 lb packs. We saw 1 of them later and he was really dragging (but this was not the guy that was carrying the 12" cast iron frying pan and fresh eggs for the whole trip in a cooler). (My pack was 24 lbs to start with 1 L of water (short hike to 1st stop with known water, and only 2 days of food). Doug Prosser and Phil Barton are probably in that same range, and I expect they are well equipped "The Philmont Way".
We're taking two 4 qt pots with turkey bags, both to boil water for 2 different components of dinner. Once the water is boiled, we pour it into the turkey bag, followed by the food. The bag sits in a cozy which gives it support and minimized heat loss.
Cleanup of the pots is to dump out any remaining water.
When finished, the turkey bag is human sumped, meaning someone licks it clean, then it goes into the trash bag.
While another piece of plastic in the trash is regretable, the amount of effort it takes to clean a pot with spaggetti reminants is likely much greater :)
When do you leave?