Bloodless balance is one of the basic arcana, gained through either one of the great tutors of Alessandria (specifically Entropicus) or - if suitably skilled - a member of the loremaster profession with well-developed opalescent spectrum. Its function is to speed up your regaining of balance whenever it is used: whether in combat, recovering from having struck an opponent with your weapon, or whether completing a complex manoeuvre. Each notch of bloodless balance you gain, to a maximum of 100%, will contribute to an eventual total hastening of your balance regain that may - and indeed often does - prove the key element in a closely matched conflict.
See HELP BALANCE for more info on the concept of balance, and HELP RESONANCE for details of the second of the basic arcana.