How do Huang Tingjian and Dong Qichang evaluate Su Shi's calligraphy?

Huang Gu said: "Dongpo's book is gloomy and sandy, and between pen and ink, others can't reach it." Although he argues that it is impossible and he has his own methods, he only advocates a broader view of law. There is something wrong with his handwriting. For example, Dong Qichang once pointed out that "in-laws writing too much is also a disease".