What do you think? Do you see a difference between combat and sparring.
I think before this matter can be intelligently discussed, perhaps we would need to agree on exactly what is, and what is not a block.
Though not directed at me, I'd like to comment if I may. Sparring, as used in the majority of dojangs/dojos, remains within the confines of a specific rule set. Certain movements are allowed, others are not. For example, in a typical TKD dojang, sparring probably wouldn't include ground fighting as it is generally outside of the parameters that are taught. Various rules are enforced as well. Combat on the otherhand, is a free-flowing, chaotic event wherein no rule set exists (at least upon the part of the attacker), nor are specific techniques not allowed. Combat can/does usually take place in situations/environments that are not trained for in typical dojangs i.e. enclosed spaces, outdoors, dim light, sloping surfaces, improvised weapons etc.
Perhaps, for the perspective of TKD, a 'block' can best be defined as a 'movement to intercept and/or deflect an incoming attacking movement'. Would this be an acceptable starting point? The only problem that I see with it, is that while a 'block' can be done on occassion in combat under the above definition it still at a distict disadvantage since a reacton will always be slower than an action. The karate phrase, 'there are no blocks in karate' bears close examination. It can be true, though somewhat misleading depending on how you view it. Typically, when training in Okinawan karate, I was always taught that a 'block' is actually a strike while often offering protection from an incoming attack.
As an example, the S.P.E.A.R. technique or the elbow jab cover are both protective covers (block) but also offensive strikes. Either of these 'blocks' effectively protect the head from an incoming attack such as a haymaker using what is termed the 'flinch response'. But at the same time, they are devestating counter-attacks designed to allow multiple follow up strikes (if necessary) in the shortest amount of time in a very brutal, fight-ending manner. They are so effective that they have been adopted in MANY L.E. training programs, including ours. The S.P.E.A.R. is fully capable of fracturing the clavicle, breaking the jaw, breaking the nose and fracturing the eye socket in rapid succession in just over a second. It will damage those specific parts of the body to a greater/lesser degree based upon the force used in the defense. In short, it is desgned to end the fight
now. Karate, at least the arts I was taught, was very much the same way. A fight was suppose to be over in just a few seconds (typically an attack is statistically over in 7 seconds with injury occuring in the first 3 seconds) and the attacker was suppose to be broken and physically unable to continue the attack.
In this light, we can take a movement such as the one usually labeled a 'low block'. This is typically taught as a defense against a low punch or an incoming kick. I've discussed at length that a low block is an extremely poor choice of defense against an incoming kick. However, the 'low block' makes a particularly devestating movement (read: hammer fist) to the lower anatomy of an attacker at close range.
What I'm saying is that a 'block' should
not be something that in-and-of-itself is a purely defensive movement. It needs to be defensive-offensive in nature and execution. In otherwords, the block itself should be capable of ending the fight or
at the very least, in addition to causing damage to the attacker also set up additonal attacking movements.