Exchanging blows generously, which is not uncommon in some other martial arts, is unthinkable in Shaolin philosophy, because a Shaolin disciple always assumes that an opponent is competent and able to inflict damage with just one blow.
The Art of Shaolin Kung Fu: The Secrets of Kung Fu for Self-Defense, Health, and Enlightenment (ed. Tuttle Publishing, 2002) - ISBN: 9780804834391