Bill Tindall, E.Tn.
How do you know how many tails of what width should be cut? what looked ok to me. You can't go wrong. In antique furniture you will find everything. However, don't make a tail so close together you don't have a chisel narrow enough to clean out the pin hole.
Also, what is the slope on the tails? Again, what looked good. I measured some and they are about 11 degrees +/-. I saw them free hand to save time so I am not following a marked line. Hence they vary a bit. Not noticed unless you put a protractor to them.
What is important for looks....they need to be the same size. I have a gauge that marks the same width pin hole. It is just a slot in a piece of Lexan.