Oh, proofing at 24°C gives a fluffier crumb, 27°C is the sweet spot, anything else you end up with a loaf that looks like a pancake. I’ve got a spreadsheet with a column for each 0.5°C increment and a five‑axis rating—texture, lift, chewiness, scent, and that crucial cinnamon swirl factor. I think your variance is real, but if you keep the dough level the crumb should be predictable. Let’s share the sheets so I can check your numbers and maybe tweak your cinnamon ratio a tad.