A strategist is one who plans the mission, what the missions ultimate goal and what the manpower and equipment requirements are, i.e., what armor, infantry or air forces are required to fulfill the mission strategy.
The tactician takes the strategists plan and puts into use with a tactical attack plan using the resources provided and looking for weaknesses in the enemy alignment.
The best strategist of the war had to be General Eisenhower specifically for his D-Day plan and the the push to the Rhine to end the war...he was under pressure by Washington and Allied leaders to end the conflict within one year of invading France according to research. Further, after the defeat of Germany, it was determined that Japan had to be brought to surrender with 1 year after the defeat of Germany and though it ended much sooner, invasion plans for Japan commencing on Nov 1, 1945 were formulated and approved by President Truman in July 1945....sorry I got off the path here!
As for a tactician, Rommel was an excellent one, but Montgomery for all his faults used limited British/Australian forces to outmanuever and defeat Rommel in North Africa, so he had to be the better tactician. Another one to be considered would be Patton, he knew how to find an enemy weak point and use it to outflank and outmaneuever their positions.
An interest in World War II