Geez, 11 days, single portage. A wee bit to much weight IMO. Not only does the fun factor sound like it might be reduced the "hurt" factor would rise.

Besides, with the lighter loads you are likely to breeze across as opposed to the big loads where you will likely be having to set stuff down before getting all the way. Thus probably not saving as much time as you think.

I typically run a fishing line (often pulling a deep crank with a big lip.....lots of drag on the boat) and I like to run the shoreline plus I always double on my portages and yet I still usually rack up a good day mileage wise.

Here's what I do to accomplish it.....I get up early, usually while it is still dark and eat and break camp and am often paddling while the mist is still on the water. That is a special time of day to be dipping a paddle trust me. All is still and quiet more often than not. This early start takes advantage of calm conditions when you can really roll 'cause as we all know it's gonna blow by 2. Then it is common for me to run late unless I'm worried about campsites. You can rack up some miles like this. I do like seeing new country. One bit of hard earned advice.....if you are a food stasher like me make sure you have a reflective marker to hang in the tree to mark your placement or else you may be "delayed".

Prouboy is right BTW, I'm not much fun around the campfire.  I'm usually in the sack shortly after dark if I'm not still fishing.

I've done several trips of 2 with a duration you suggest. My opinion: unless you eat tofu, single portaging will be pretty tough with the gear/food you will need. I'd recommend taking a little more time on the portages.

After a few solo trips I found the thought of a large group (anything more than three) doesn't thrill me a bit. Also you realize the double portage is not that big of a deal. I like being able to do longer trips and seeing more... and sometimes seeing more is part of that second trip across the portage. Something I believe Marlin was saying... The only time I like to move a little faster is going into the BW to get past the crowds.

I trip with my now-19 year old son each summer, usually 8-11 days.  We could single portage since Ben's quite strong (6'2", 240 pounds, offensive tackle).  He can easily carry 120+ pounds across a portage, but he doesn't like to.  We like some creature comforts and fish quite a bit, so we usually have enough stuff to double portage fairly easily.  Sometimes, one of us will double and the other single if one of us feels particularly strong at the moment, or just too darn lazy to double it...

Food for 2 people for 11 days should weigh ~25lbs.
Total kit for 2 people should weigh ~50lbs.

Lots of room for single portaging with a single 60-70lb pack and a 5 - 15lb daypack + 50lb canoe.

Another alternative is the 1.5 portage.
Buddy1 takes his pack all the way.  Heads back for the canoe with is waiting at the halfway point.
Buddy2 takes the canoe half the way.  Leaves it for Buddy1.  Heads back for his pack.