Although it seems more complicated, you should know that it is not - I really call it the "convenient" method of making jam - you boiled it a little and left it .. :)
But I guarantee you will have a special sweetness - aromatic, bound, beautiful and delicious - no chemical will make such a consistency and color.
For simple cherry jam, I would recommend using only lemon juice - put the rest of the lemon pieces only if you like the taste in the jam.
Good appetite!