It depends on what you mean by "principles" and "footwork." Also: who's doing the fighting?
I posted the original quote so perhaps I should clarify my statement. I don't see much of a distinction between "bare knuckle" fighting and Xing Yi as long as the "bare knuckle" fighter uses the same internal principles. This would mean using the whole body to generate power, using sketetal structure and angling to create the best line of attack and defense, the use of forward pressure, and changing sides of the body while moving. A fighter may not necessarily explicitly understand "rise, drill, fall, and return" to instinctively apply these principles - but it can happen nonetheless. In terms of footwork, Xing Yi's "chicken step" is essentially a step-through designed to facilitate the principles listed above, which can (and should) occur in any bare knuckle fighting tradition, irrespective of its particular tradition.
I've experienced good Xing Yi but have seen one good bare knuckle fighter, so don't take my statements as gospel. One similarilty which struck me, however, was the use of turning the spine to effect short power with uppercuts (as with Tsuan Quan and Hung Quan), as well as the principle of not collapsing forward pressure (i.e., keeping the arms extended throughout a movement) while attacking. Granted, the bare knuckle figher in question is in fact an internal boxer: my original statement was merely that he showed me how easy it was (for him) to switch from one style to another as long as the underlying principles remained the same.
Best,
Steve Lamade
