Without explaining why this works I'll just explain how to do this.
When a worker is returning gathered minerals (it is returning whenever and
only the
RETURN CARGO BUTTON IS AVAILABLE). This button is default to C or if you are like me & use the grid layout then it will be D.
During the return cargo phase hold down shift, right click on the mineral patch this worker is mining at, now continue to hold down shift and issue the return cargo command. Do this as many times as you can during the return cargo phase and the orders will remain for 1 trip per each shift right click/shift return cargo.
A simple macro that could issue these commands 15 times each (as 33 waypoints is Starcraft 2 is the maximum)
(!empty($user->lang['CODE'])) ? $user->lang['CODE'] : ucwords(strtolower(str_replace('_', ' ', 'CODE'))):
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
SHIFT + RIGHT CLICK CURRENT MOUSE LOCATION
SHIFT + C CURRENT MOUSE LOCATION
Any more then that then the cycle will break.
Now for the WHY this works, during the last phase of the return mineral cycle your worker regardles of race holds he mineral for about a 0.2 sec moment and for whatever reason issuing the command listed above removes this useless animation speeding up resource collection.
This is known by Blizzard as an animation flaw and is not a bannable offense, no tournament disallows it and the GSL has not frowned upon it, expect to see this in pro play until patched.
Here is a video if you are struggling.
[youtube]http://www.youtube.com/watch?v=aILpxVKuc5s
[/youtube]