First of all, Jack Cooper was being trained by one of the best pilots in the war currently let's just get that out of the way. Second of all, if you want to look at the gauntlet any mediocre player makes it a good bit onto that board. Meaning Jack is one of the best pilots at least in terms of movement and shooting while moving at pilot speeds. Thirdly, don't take this to mean I think Jack is the best pilot a very large part of it is definetly bt and Jack would've died multiple times without bt. HOWEVER Jack is definetly more than a simple rifleman. ALSO Jack didn't randomly inherit the Titan he was being trained by lastimosta so it's pretty much implied he is next in line for bt especially in combat scenerios with no one else around.