Before figuring out this problem, let's take a look at the difference between the two. Using a pen is a process of brewing, considering and then putting the strokes on paper after fully understanding and full of confidence in the content to be expressed.
What about gestures? It's what the strokes look like after writing. We readers can see gestures intuitively, but readers can't know the brewing process of using a pen. They can only use gestures to explore the author's thoughts and ideas at that time.
So we must subdivide which is the more important link between the two. I think using a pen should be the most important thing. After all, it is related to the quality of the whole work.
I say this because I have carefully experienced the difference between the two in the process of practicing calligraphy. If you don't have a good concept of using a pen, just practice hard. The more you practice, the more mistakes you make, which will affect the progress of learning calligraphy.
If you want to make the strokes written have soul and interest, you should pay attention to them before you start writing. Do you want to write about their dignity mainly from the perspective of content expression? Or do you want to write about its agility? Take writing a list book as an example. Generally, single books are magnificent, so when dealing with them, don't write very delicate feelings, otherwise it will destroy the overall feeling as a single book.
If you are creating a running script, then the grasp of the whole stroke is reflected in your pen. You should know exactly where to break lines, where to highlight lines, which words should be capitalized and which words do not need to be emphasized.
Using a pen will also have habitual and accidental problems, that is, you will be prepared again, but the atmosphere, environment and your mood at that time will affect the quality of using a pen. Therefore, I think that when learning calligraphy, we should pay more attention to practicing using pens.