Interesting comments and wisdom from all. There will be different most efficient apptoaches depending on area, routine, and climate.
I can add a few regional observations. Here we have very strong summer drying conditions (usually). (2 cuts of hay, maybe 3 if you push it) And an extreme seasonal variation in climate. There are definitely best times to do different work.
Cutting wood when leaves are on the trees would be considered desperate due to some lack of organization, or as part of a logging operation. Why? Reduced drying time, early spring is frequently dry, and no shade from trees. Sweat, mosquitos, and if so blessed, black flies, deer flies, wasps, hornets or woodticks. No bugs in the late fall and winter, and low risk of sweating overly. Poison ivy drops it’s leaves. Assessment of snags, visibility and mobility in the bush is greatly aided when things aren’t obscured with foliage. Brush will weigh less without leaves. Arguably less environmental harm when the bush is dormant, no nesting birds, critters or active insects.
In my observation wood splits far more easily when frozen hard.
The timing to cut in fall and winter, split and pile before snow melts dovetails nicely with the general routine of work, and serves as good exercise in a time of year when people tend to be most inactive, and the day length has increased appreciably.