Originally Posted by mrmyz
your right on its like comparing a rifle to a shot gun blast but because the elbows arent padded you get more external damage as opposed to penetrating power. Its the same for people like me instead of doing round kicks with my shin I do them with the ball of the foot because the kicks have more penetration. In a mma application you would want this because you could call the fight quicker because of excessive bleeding. They are primarily the short range weapon of choice
As always people on these forums start to change the question to fit their answer. No one was disputing whether or not elbows were effective or not, the question was that his instructor claimed that the elbow strike was not more effective in knocking people out and in my opinion that is true. The punch or kick is more effective in pure KO effectiveness.