A lot depends on the day… A very good paddler I once knew used to say, “there are canoe days and there are kayak days…” At least for me the occasions when one really needs to cover miles fast are few and far between. I’m thinking of those occasions when everyone has to be to work on Monday, folks have loitered around camp a bit too long on Sunday morning, a headwind kicks up, many mile to go… sustained speed then matters. Sea kayaks can do that, of course, but many solo canoes can do a pretty good job of that as well, provided the paddler is willing to just hunker down and paddle the thing.
Wind, to me, is a big factor with solo canoes. Solo canoes just show more square inches to the wind. (And on those windy days the extra horsepower of a tandem canoe paddling team really helps, also.) Kayaks have the speed advantage on windy days. Really big waves advantage kayaks also, but not as much as wind.
BUT under normal conditions, I can’t begin to count the times I’ve paddled my solo canoes in mixed groups, been passed by a few sea kayakers who then feel they’re "fast"in an undeclaired race, only to catch up to them doing leg stretches on an island ten or fifteen minutes later. Because they need to do leg stretches. This can happen three or four times times a day and we all get to camp or the take out together. My point is that you don’t cover a distance any faster if you have to get out often because your boat is not comfortable enough to sit in for the distance. Well conditioned kayakers have become accustomed to cramped conditions and can take it, but the average ones usually can’t. Solo canoes often get to camp first at the end of the day. Comfort can translate into speed. 80% top speed and steady steady steady usually wins the day. I don’t know any kayakers who take lunch while on the water, canoeists do it all the time. Maintain an even strain.
Any larger group moves more slowly - its hard to get a group to average more than about 3mph over the course of a full 8 hr. day. Its the potty breaks and the slowest common denominator that sets the group pace. Under those conditions waiting is a pretty common situation for most of us here, I’d venture to guess. (I used to know a fellow who claimed he only smoked because it gave the youngsters a chance to catch up. )
And just minutes ago I recieved an ad from REI encouraging folks to get out on the water - they pointed out that it could be done with either a kayak or a paddleboard. What’s up with that, anyhow?