No 00 brushes; the smallest brush was #4 sable.
I paint the small area and then paint the larger area up to it. If you have 2 large shapes with a small gap between, it forms a thin line or small shape between. I do not even own any brushes smaller then #2 flat.
Yes, the size was for mobility, frugality and time. Smaller canvas is easier to carry, cost less, uses less paint and I find I just can not cover a large canvas in a hour. Some times these are complete failures as paintings. Even these I posted, I am not sure why I show them. I always look at these after and wonder what I was doing.
But it is always time well spent in observation. The biggest frustration about open figure sessions is I have to have control of the pose and lighting or I am frustrated the entire time. And I can't always have that control since there are several others attending the same session.