Having primarily traveled in larger groups and single portaging for much of my tripping experience, I can honestly say that I understand your concern.  Trips of late have been with fewer people, 4 in 2 canoes and up to 3 in a single canoe.  Often we double portage at the beginning of the trip due to the food pack's weight, then are able to single portage for the last third of the trip.  Since I usually carry a canoe across first, I look at the second trip as a nice walk to see what I missed.

For 11 days, my food weight would be more like 45-50 lbs. for 2.  We don't bring that many fresh foods, but we like to eat well and don't bring much dehydrated stuff.  I would say that Preacher's weight quote of 25 lbs. is ultralight.  A Kondos or CCS food pack sould all of your food easily.  I suggest each person pack in own daypack/overnight style pack with room to put 1/2 of the shared gear.  That should result in an easy second carry.

Other than that, I'd suggest looking at cooking/crew gear that you usually bring and pare it down.  You might find that you don't need a large pot, or that it doesn't make sense to put cooked food from a pot into 2 bowls, etc.  Perhaps a dining fly is a luxury you can do without.