Most musicians do not know a great deal about good notation; they simply take it for granted. They do realize that it is not good though when notation cannot be read fluently. Notation is something for specialists and needs a lot of expert knowledge. The currently relevant reference book for notation is "Behind bars" by Elaine Gould.
This work is considered THE dictionary for notation. Yes, there is something like notation "spelling", and this work - quite a bulky volume with around 700 pages - is the reference book. With a price of 70.00 British pounds it is not something each musician might want to put on the shelf. But if you have the chance take a look at it - just for fun. You will be amazed!
When you are writing your scores with capella you do not need to know most of what you find in this book. capella correctly applies all rules. You do not have to think about stem directions, position of articulation symbols, length of ledger lines and so on. On the contrary: It is rather difficult and requires intervention by hand to do something wrong in capella.
Our slightly flippant name for Elaine Gould's book is "The Bible". We strive to make capella correctly apply all of Elaine's rules. Well, we are not done yet - but we are working at it!