Can learning brush regular script improve the level of hard pen calligraphy?

In my opinion, of course, because people who know it must know that hard pen calligraphy and brush calligraphy are mutually transformed. The original form of calligraphy was Oracle Bone Inscriptions, and a large part of Oracle Bone Inscriptions was carved out of stone. Therefore, from this point of view, hard pen calligraphy is the ancestor of brush calligraphy, but at the same time, brush calligraphy has occupied a dominant position for quite some time in the past, so it has been well developed. After the precipitation of the times, the essence of the paste is vast. In modern times, we have gradually forgotten the writing brush, creating a good development space for hard pen calligraphy. Therefore, writing a hard pen or writing a soft pen is just a different preference in the new district, and there is no essential difference. Of course, objectively speaking, the artistic expression of brush calligraphy is definitely greater than that of hard pen. So I suggest you practice soft pen calligraphy, as long as you really know the rules, the writing style can be completely transformed! I wish you an early success!