Direction changes demand more skilful movement than simply charging along a straight line. It’s also harder to maintain your speed when you are forced to change direction. Movement pressure is created when you force your opponent not only making him cover the distance, but also by forcing him to change direction. Actually speaking, both the choices are good but, that depends on the game situation.
Moving your opponent through to the diagonal is good because he must move to cover this longer distance. Also, moving him to a different corner is also advisable because, you force him to change direction.
The two basic rules are, if your opponent is agile but lacks in speed, make him move the long diagonal more. If your opponent is fast but lacks agility, then make him move to different corners.
When your opponent is under pressure in a corner and is unable to make a proper recovery to the center (base position), then the best option is to play the next shot diagonally since he has not recovered yet, he will have great difficulty covering the longest distance. This is an excellent example of how to make use of your opponent’s late recovery into a winning advantage.