The jab was considered the most important weapon in scientific boxing and in a striker's arsenal, yet it is often misunderstood. The jab has become for many coaches the go to advice; if in doubt, jab - but this is more hazardous than simply covering up would be as poor, predictable jabbing often leads to easy counter punching from an experienced opponent. Watch this poor sap come out of his corner and attempt to "establish the jab" and receive a Cross Counter for his troubles:
First Punch Knockout (via TheMightyUnderground)
The key points that make effective jabbing so important to the fight game are that it:
1) Travels the shortest route as it is closest to the opponent
2) Travels inside of the opponent's rear hand, meaning it will beat almost every punch except for the opponent's jab
3) It can be thrown moving left, right, forward or back
4) It can stun the opponent and obscure his vision for the split second needed to land a follow up punch
5) It can be used as a direct counter when combined with a slip.
On offence the jab must be used extremely carefully in order to avoid eating a counter such as the one mentioned above. The brilliant boxing coach, Edwin Haislet wrote in his 1940 book "Boxing" that there are eight major counters for the jab and also listed several dozen minor counters in less detail.
Clearly jabbing blindly is a minefield.