It's not enough to think you can slow
down in enough time to flatten your wake when you see one of these
canoes "out there," because they're so low in the water, you might nit
see them at all.

So don't. Canoes, kayaks and the like can handle wakes. Well, ones from a
boat at a reasonable distance of course. If you're in an area tight enough
to be a problem then it's probably already a slow or no-wake zone. If they
kayak operators aren't smart enough to turn into the approaching waves then
a dunking or two will either encourage them to learn or get out of rowing.
Now, a rowing shell, scull or the like deserves a bit of caution. But the
folks operating those boats are likely to be making their own efforts to
avoid areas with wakes anyway. In the few cases where they do need to
traverse a channel it's not unreasonable to cut 'em some slack. I suppose
there are plenty of lake situations were it's worse.

But tourist in kayaks, no. Barring other restrictions to the passage, and
the 'avoid collisions' rule I don't find it a good idea to do anything
different because of their presense. There's no sense in being 'mean' about
it though.