The Gooney.
I hope this reaches all of the commenters here, all very skillful and learned. The nuance suggested by these comments is breath taking. But, the penny drops,
The J, the J, the J, I have been paddling canoes solo now for 60 years, and yes, there is a powerful case to be made for the J-stroke, and it IS an essential stroke to be skillful at.
But none of you is lazy enough to suit my tastes. I am lazy, I am also a few months shy of 70 years, and I LOVE long trips and flat water AND white water.
You are nearly all underestimating the Goony, or Gooney stroke. Yes, I use the J when I pull the paddle hard enough to bend the shaft on each stroke. I DO bend the shaft. When I snap to the J side, the shaft unloads and my power of bending the shaft snaps the residual of the stroke for my correction. At my age I can maintain that 5mph in a loaded 20 foot canoe for about 10 minutes. The Gooney, hmmmm first allow me to describe in excruciating detail, for give me. Ideally my arms are ALWAYS straight. The power comes from our backs and butts. Straight arms, I lean forward slip the tip in (I HATE splashing my tip in.) and pull long, parallel to line of travel, only a little catch angle, all the way to the stern exit, feather the paddle back, with the tip making a broad sweep and at touch or an inch or two above the water for the return, arms always straight. None of this lifting stuff, I am lazy. From the feather the tip slides smoothly into the water for the next stroke, no splash, silent. Now, every second, third, or fourth stroke, when the paddle is behind me, I go thumb up, wrist square, (if on the right side) left hand almost in right pocket and right arm straight and behind me. With a 62 inch paddle, 60 inches behind my right pocket, the force needed for a correction is in ounces, the pry is between thumb and fore finger, the hand between shaft and gunwale. Remember, I am lazy.
Yes, it does interrupt cadence, costs about 1/2 to 3/4ths of a stroke time. But I am also only doing it as required. At low speed, every other stroke, just a bit, at faster speeds every 3rd or 4th stroke.
Turning your wrist upside down and backwards for a J , 400 to 600 strokes to the mile, X 20 or 30 miles, 3,000 to 5,000 J-strokes in a day? 10 day trip? 3 month trip? You may as well amputate my arm to the elbow.
Flat water? I switch paddle. Save calories, wrists, and gains essential skills for white water. You must be able to, with complete confidence, switch paddle in white water in cadence. There is no time to miss a stroke. The reason for cross arm strokes is again, not lose time. A cross arm stroke is half or less the strength.
I normally use the Gooney, all day and every day. Done well, it is easier, very efficient, saves my 70 years old wrist from permanent damage, save calories on long trips. (Calories? Think about a 20 or 30 pound food difference for a long trip? i.e. Green River, Utah to Page, Arizona? the Green, the Colorado and Cataract Canyon, to Lake Powell to Page about 400 miles?) Switch paddle and learn the Gooney. Learn to be lazy.