I planed a lot by hand before I could afford a secondhand planer/thicknesser. Because that was what I could afford to do. It was doable but the problem was that I spent so much time planing that I just couldn't possible make the stuff I wanted to make. There wasn't time enough.
We need to remember that pure hand tool work was in an era when lots of things were different.
A joiner usually worked in his own kitchen by the light from the open fire except for those few hours a day when there was some daylight coming in through single glazed windows covered by a thick layer of ice and condensation. In our modern world that would be a serious fire hazard but in a time when someone was in the kitchen which was often the only heated room all day and night looking after the fire it was significantly less of a fire hazard than it would be today.
Back then most joiners would also have either an apprentice or a son or a farmhand or even his wife helping him to and fro with less qualified parts of the job. You had to be two persons to use the big scrub plane efficiently. One pushing and one pulling. Without a helper you couldn't prepare stock fast enough even by the standards of the time.
Timber was cheap and plentiful and people were very good at planning ahead. Materials were often selected in the woods and either sawn or split and hewn (pit saw blades were costly) to roughly suitable dimensions for the purpose in mind and then dried. Therefore there wasn't that much need to resaw timber. If a boaŕd was too thick it was very often hewn thinner with an axe as the material was cheap while bow saw blades and files were expensive and not to be worn more than necsessary. Most woodland was village commons where any villager could take as much as he needed and there was timber enough for everyone. Only the straihtest and most easily worked timber was chosen for joinery. Straight timber with smooth grain is much faster to work.
People were skilled with axes. Honestly how many of you would think of crosscutting a 6x12 inch beam square and smooth with an axe just to save wear on the saw blade. Or to hew away the waste from the round side of the last board to come out of a log just to save wear on the valuable pit saw. In the past that was just a normal everyday occurance at any construction site or any shipyard and many joiners dabbled with some house or ship carpentry or boatbuilding in the summer months. The axe and chopping block were just as important parts of a joiner's workplace as were the workbench and the long plane.
Theese facts hold true in Finland and most of Sweden but I rekon even in Britain things were very different 200 years ago.
You make very valid points and your post makes a very interesting read.
The way things are going, the UK will be operating in this mode again quite soon !