Adze/axe much more in use for rough work?
But there are nowWhat I found (see photos earlier) was simply that the scrub was much faster than a jack, for that sort of work. In fact a jack would hardly touch the rough surface and just clip the high points. Also would get blunt very quickly - the scrub cuts deep into the clean wood underneath avoiding nearly all the grit etc. n.b. planing across the grain is fundamentally less work because the shavings roll more easily.
Basically the deeper and narrower a cut the more material you can remove, for a given effort.
There's a point to this that you're ignoring, Jacob. The nicholson text was written when it would have been important to do this efficiently. All of the short planes aside from the two hander continentals were developed by a company specializing in site work and specifying that the short narrow plane was for site work. It's more important that it fit in a tool box and not change with the weather with disuse because it may not be used often.
The lack of the short planes along with the technique that nicholson mentions (instead of traversing the work) is important as it reduces effort and cuts time. You can use a coarse jack plane and go straight to a thickness planer (it may never be on some peoples' radar to dimension entirely by hand, but it's very practical to not have a jointer and use a jack plane. It removes wood with less effort, more accuracy and can fit better even in a power tool rotation.
It's so efficient that sometimes when I get full-on into the joinery part of a case, I get resentful that the ease of dimensioning by hand has to wait until the next project. With a short narrow plane, you're instead left with a tool that increases effort due to lack of controlled rhythm and you have to do a bunch of checking to make sure you're not creating hollow areas - something you don't really need to do with a jack.
As per the instructions of arm length strokes, I started (and before reading that as someone else pointed me to it) liking just initial high points and then walking the jack up and down a board so as not to tire in the arms. I was wrong about it, just as anyone here who thinks a scrub is better for stock removal than a wooden jack is off due to poor supposition. I went to the method that nicholson describes and counted time and it's far more efficient. And thus sold my scrub planes.
A lot of people get into this hobby believing that the "jack plane is the jack of all trades". It's a stupid thought, but it sounds witty, I guess.
It's just an instance of if you want to learn to do something well, then first turn to the people who had to do it well and see what they did. Then, after that, you can see if there's improvement.
All of the little nuances like this are the difference between stabbing around and doing some work by hand from time to time (all the way down even to using a metal jack instead of a wooden jack - the effort level is so far different that anyone who spends time with a wooden jack will then use a metal jack and say "ew, I just can't keep wax on it fast enough"), vs. becoming efficient and choosing to do the work by hand, accurately. I may be incompetent with power tools (That's probably true), but I can thickness a board to a mark by hand and have no variation greater than 5 thousandths just as a matter of routine. It is the same as taking a brisk walk, and I'd hate to go back to ideas that became popular post-nicholson when nobody was actually doing the work.
If a short plane was the way to go, it would've been in nicholson as such solely due to economics.