Changes rapid movements in the output machine code, into feed moves.
Found on the Linking tab, the High Feedrate Mode settings allow you to change the output machine code for rapid movements, typically a G0, into the code for feed moves, typically a G1. You may choose to do this because of the differences in how your machine responds to rapid vs. feed moves.
If you are cutting at 300 IPM, it may be more practical to maintain that feedrate for your rapid repositioning move, rather than change into a rapid rate. For very short moves, the machine may never actually achieve the rapid rate. Maintaining the same feedrate may improve the flow of positioning the machines axes.
For a rapid 3 axis move, most machines will move all the axis at the same speed. If the position requires all the axes to move an equal distance, all the axes will reach their target at the same time. If one axis distance is longer than the other two, the move will look more like a "dog leg'.
For a feed 3 axis move, the machine will the reduce feed per axis, so all three axis meet the target at the same time. Instead of each axis moving at 300 IPM, the distance traversed moves all 3 axis at a synchronized 300 IPM.
It may be possible that a straight line rapid move might avoid a collision with a standing boss. But if it moves in a "dog leg" fashion it might collide with the boss. Forcing the move at a fast feedrate, insures you get a straight line move between the 2 points.
Nothing will appear differently on the canvas. You will only see the results in the output G-code program. The post processor configuration can also be customized to do high feed automatically.