Thanks for the feedback, folks!

Actually, a canoe with the weight in the middle will handle better than a canoe with the weight more evenly distributed along the length.  That's why whitewater tandems put the paddlers as close as possible together.  The lighter the ends are, the easier it will turn.  Someone who remembers high school physics could explain this better than I can ... something about moment of inertia ....

My purpose stems from a trip some years ago in this boat.  My partner outweighed me by 70 lbs and the only way we could trim the boat was if he was in the stern. 

When I was in the stern, we couldn't get enough weight back far enough to trim the boat, so it was bow-heavy.  I'm planning a trip this spring with my brother, who's 30-50 lbs heavier than I am.  Same problem, and I want to be able to switch places.

But the more I think about this arrangement, the more it seems like the boat will be harder to handle because both paddlers' control strokes will be close to the center instead of the ends.  It definitely calls for testing before committing it to a trip.

Referring to one of ST's comments, I have a Bell NorthStar (16'6") that I use solo.  I don't paddle it backwards; rather, I remove the bow and stern seats and install a seat about 18 inches behind the center thwart.  There's plenty of room for moving packs around, and if I paddle it empty, a day pack placed all the way forward trims it pretty well.

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