Two questions:
1) What are the best ways to increase protein when adding carbohydrates such as sweet potatoes or turnips? In the "old" days per my old 1942 book on keeping poultry on scraps, where they were dealing with wartime rationing, there was a lot of fish scraps being cooked into submission and mixed with mash (don't really want to do that). Does one maybe switch to a game bird ration for a period time? Other supplement?
That would depend a lot on how many turnips/sweet potatoes they would be eating. If I were giving it as a snack type item, I would leave them on their regular feed. For chickens we do 21% protein feed after 4 months old, year round.
2) Unrelated question, probably answered here before but I can't seem to recall details - meat production data is straight-forward - you can weigh each bird. But what is the best way to track egg production (including beginning to lay again after moult) without trap nests? (I know you can track how long they are in mount and check pelvic spread, etc., but I figured the proof is in the eggs.) Perhaps if you have a sense of who lays what kind of egg, and the colors are different in a given coop? I saw a photo of a coop (sort of a "glamour shot," really), and there was this cute chalkboard with egg talley's for each (named) hen. I found myself asking "How on earth do they know?" The photo implied that each hen had her own nest (which doesn't really happen). It bugged me, and made me want to ask here again.
Without trap nesting you aren't going to get accurate numbers, but if you have smaller pens, you can get a general idea of laying. When I have a pen with 8 hens and I'm getting 4 eggs every day, then I have a good idea that they are probably all laying every other day, because I know my breed's characteristics, and my flock's characteristics. It isn't as scientific or accurate as the spreadsheet data you are making for your flock, but I've made breeding decisions based on this type of casual observation of egg laying and it has worked fine. Just depends how much data you feel you need, what accuracy level that you want. If you want highly accurate, trap nesting is the only way. Some people have put food coloring in their hens' vents for keeping track of egg production, but I have not found that to work any better than observing which hens I find in nestboxes and keeping track of how many eggs come out of a pen every day.