help with stretch and fold please!

The last couple of days I've studyed the stretch-and-fold/French fold videos, read the discussion threads that deal with it, printed some things out to study some more, and then reviewed everything a few more times.  I have the impression that once you get it, it's really too simple to even explain adequately (if that makes sense). But I don't think I've got it yet. Today I tried to apply the techniques to a double batch of Struan (the recipe posted under Favourite Recipes) and the results were not stellar (loaves were smallish.) So I could use some help figuring out where I went wrong.  I should explain first that I probably introduced too many variables when I should have stuck with just stretch-and-fold. Instead I also tried starting out in a non-preheated oven (a whole other discussion); and, since I had some potato cooking water in the fridge, I substituted that for the water. It may not have helped that I doubled the recipe either; it meant that I had to cut it into 3 pieces which may have undone some of the efforts to keep the dough structure intact. Anyway, here are my questions:

1. The recipe said to knead the dough. I didn't. I mixed with a spoon, then by hand, mostly trying to get everything to stick together without kneading. Then I let it rest for about 10 minutes. At that point I wasn't sure how wet it would be because I hadn't handled it very much yet. It didn't seem as wet as the dough in some of the French fold videos. Is this correct so far? Should I/could I have done a little kneading? Should I have added any water for a dough that looked more like the Bertinet sweet dough? Is it okay to substitute alternate techniques when a recipe tells you to knead, or is it better to use recipes that are designed for stretch and fold?

2. After a 10-minute rest, I just folded twice with one turn and put the dough back in the bowl. It was pretty tacky at that point and seemed to want to stay in a ball (not stretch).  I let it rest about 20 minutes, then folded again.  This seemed like it could be a long labour intensive process.  Should I have done a few more folds at the very beginning until the dough was more elastic? I was afraid of overhandling.

3. I let the dough rest again for about 30 minutes, then sprinkled flour on my work surface.  This time I gently flattened the dough and stretched it out into a thick square.  It handled nicely. I folded the sides over on each other, turned it and folded the two ends over each other, and put it back in the bowl.  I poked it here and there to make it look like I knew what I was doing but I suspect that didn't add anything. At this point I thought I would just let it ferment for awhile, till double. Should I have done more rests/stretch-and-fold before leaving it for an hour? How do I know when to keep up with intermitent folds and when to trust the dough?

4. I was starting to run out of time so I left the bowl covered with loose plastic and a cookie sheet over that in a sunny spot in the kitchen.  It probably got to be 75 or 80 in the bowl, and it was doubled in about an hour. Was it a bad thing to leave it in an extra warm spot?

5. Now I had to cut it into pieces, since it was a double recipe (6 cups flour plus other grains). I hate cutting a round mound of dough into 3; impossible to divide equally. At this point I was confused about the best way to form the loaves. I also wasn't sure how to deal with the middle piece which had been cut on both long sides so that all the holes were exposed.  I folded one piece like a letter (2 folds, no turns) and let it rest, then I rolled it jelly roll style as in jmonkey's sandwich shaping video. I found it hard to get it elongated and to tuck in the ends, maybe because I was worried I was destroying the structure. It would have been happier as a boule I think.  The other two pieces I tried to roll and get surface tension by stretching it under and pinching a seam. One of those I had to bake free form because I only have two pans. I didn't feel that comfortable with the degree of surface tension.  The outside seemed a bit weak to me. Corrections here? How do you get that tight jelly roll while still having the dough long enough to fill the ends of the pan? Is it possible to make it too tight, thereby ruining the airpocket structure? After cutting the dough into pieces, could I have done anything to increase surface tension on the cut sides?

6. At this point I put the loaves in the oven for final proofing. I had warmed the oven a teeny bit, then added a bowl with boiling water for humidity. They rose okay (one hour) although I might have let them get a little higher if I hadn't had to go out.  They crested over the pan.  When I slashed them though, they seemed a bit weak and then deflated a little with the cuts (the knife was pretty sharp). This surprised me because I don't think I had overproofed. I put them back in the oven and set the temp to 350 as per the recipe.  I left them in my husband's charge at that point, so I didn't watch what kind of oven spring I got.  Seeing the loaves when I returned, I don't think there could have been a lot.  Should I have turned the oven to a hotter temperature to start, then lowered it after 15 minutes or so? Should I have preheated and not listened to all those good folks who have been saving on energy while still enjoying great bread?

As usual, the results tasted better than they looked, especially with creamy chicken wild rice soup. I just would have liked to have put a nice big loaf in my freezer.  Any questions answered or errors spotted would be appreciated!