That is kinda funny you bring this up…I am helping a co-worker start to plan a trip for 2009 and trying to teach her how to pack. You can look at this whole thing one of two ways.
First if you want to pull on 2 suitecases per person pack 8 days of clothes for cool-summer time and then add in like 2 jeans, sweetshirts, and coats. but then you will not have alot of room for the bring backs.
or the second way you can look at it is yes you would have to do a little landry but you could pack cool-summer things for 4 days and add a pair of jeans and sweetshirt and long sleeve shirt. one morning take 2 hours before going to the park and play in the pool and do the landry. this way each person has their own suitecase and then one extra one for the little (or BIG) bring backs.
As far as packing now you can do that one of two ways also. first pack non wrinkle things and toss in a few dryer sheets…this will keep them smelling fresh and such. this is what i do sometimes…but then again my bags are always packed for disney. and secondly you could just get a tote and toss the stuff in that you are going to take. put the tote in your room so no extra stuff is put in or taken out and then it is all together when you are ready to pack right before the trip.
another tip for you is that when me and my family take a trip to disney that is when we get new undies and socks. we toss out the really bad ones before we go and then use the new ones while we are away and when we get back we have the new to use until the next year. Just a word of warrning if you are flying TAKE THEM OUT OF THE PACKS so that no one knows they are new. Last year I took them out but my sister did not so her and my two nephews did not have any socks or undies because someone at the airport in Phily stole them with some other things.