First, let me say that I'm a solo canoe, rather than yak, paddler.

I think it also makes a difference as to which type of single-blade paddle you use.  My personal preference is a bent-shaft.  (I use a Bending Branches wooden model ... I just love the rebound spring effect when you put some power into your stroke!)  It could be me, but I feel that my choice makes some steering strokes more complicated.  So rather than worry about it, I do a lot of hit-and-switch paddling, typically 3 to 4 strokes per side.  Moving slower, I may use a modified J stroke or a pry stroke, but since the adjusting stroke kills some momentum I'll not do that if I'm trying to make time or paddling in windy conditions.

IC is right about a double-bladed paddle taking different muscles than a single-blade.  I seem to be able to paddle all day with little fatigue with a single-blade (because that is what I'm used to).  However, I've been in few situations (wind or current) when I'd liked to have used a double blade to maintain both power and direction.  I've felt a few times that if I missed a stroke in a cross-wind situation, I could be in REAL trouble.    However, the "orbital" shoulder rotation difference to use a double blade kills my right shoulder in just about an hour.  So, I've been working with a re-hab specialist for a few weeks to see if I can get beyond that.

In any case, I'd like to hear how folks content with narrow channels with a double blade.  I can envision some issues with paddling up Cutty Creek toward Baird that could get a little dicey because of the width of the channel.

BTW:  I've frequently taken a double blade as a back-up to my single blade, but rarely have used it.

dd