RE: What are gear Drives (gear Boxes) for?
Think of it this way. Speed is top end as in 3rd gear . Thrust is low end like 1st or 2nd gear in a car or bicycle. To accelerate in a car you use lower gears. Same with props. To go fastest you want high gear. Driving in low all the time limits your top speed, right? Starting out in high gear will mean a slow acceleration.