So. Opinions on both? To me I do believe that Yi was one of the most epic naval minded military minds of naval history. Further the Korean Navy of the peiod far outclasses not only their neighbors bu, modern views on technology and development for the entire region. The Korean navy several times literally blew the Japanese out of the water with superior cannon and iron arrow firepower.
The reason that Yi Sun-shin was able to accomplish such a feat was mostly due to tradition, as a standing navy had been available for centuries, and he adopted numerous tactics and ship models, including the turtle ship, from both Korean and Chinese sources. However, it's also important to remember that the admiral's main objective was to disrupt Japanese supply lines, and that because most of the fighting was conducted on land, the numerous generals who conducted guerrilla tactics against numerically superior armies and tied up resources, such as Kwon Yul and Gwak Jae-u, should also be equally credited. In fact, the fierce resistance by the army in Jeolla allowed the navy to continuously conduct operations from that region. Granted, many of the names have been lost, and Yi was certainly the one outstanding individual for the durations of the two campaigns, but his accomplishments would have ultimately meant nothing if the other admirals and generals had not coordinated the strategies as well.
Indeed. Yi Sun Shin is the only military commander to have never lost a battle on both land and sea, even the Battle of Myeongnyang where he was outnumber 30 to 1 by the Japanese.
This is certainly true, and the victory was mostly possible due to the admiral's detailed knowledge of the currents of the area.
And this without any formal military training, and having come from Joseon Korea, perhaps one of the most anti-military cultures in history.
Well, not really. Both Goryeo and Joseon had maintained substantial garrisons in the north for more than 500 years, which explains how it was able to repel numerous invasions from multiple states attacking from that direction, which continued to occur well into the 17th century. The problem was that because an invasion had never occurred from the south before the seven-year war, the state was caught completely unprepared when Hideyoshi ordered the first expedition, and although conscription was hastily introduced and the troops pulled from the north, it was too late to stop the tide, at least initially. However, after Joseon agreed to become a tributary of the Qing, the military certainly declined as there were no major external threats, but the tradition as a whole generally had been maintained into the 17th century.
But, his being sentenced to death twice and being undercut at ever opportunity by the ruling elite of Joseon goes far in telling how valued he, and the military virtues he personified, were by Joseon and it's rulers and the wider anti-military culture in the country.
Again, this shows how he was willing to go against the court if he felt that his beliefs were absolutely correct, frightening the latter because they feared a potential coup, which was certainly justified. However, as the Battle of Chilcheollyang demonstrates, the court ultimately realized that a strong leader with a deep knowledge of tactics was necessary to win the war. In fact, Won Gyun, who was the commander in that battle, personally agreed with Yi's strategies, and thought that the court's suggestions in respect to conducting the battle would result in annihilation. However, he was forced to go through with the flawed plans because he feared imprisonment and/or execution. In other words, while other relatively skilled generals working together could have accomplished similar results as well, none was as well-rounded and determined as Yi Sun-shin was.