EPTYou will spam the second worker on the patch while the other is gathering resources, and then it will look like you managed to do it right, and they will start alternating, but then on the second or third trip, suddenly one will move away and mess up other patches.
If you dont line them up at first, but just spam the second worker onto the close mineral patch from another nearby patch, that worker, even if he starts gathering correctly for 1-2 trips, will adjust his path with each trip (since he starts gathering at the side of the patch), until he uses the closest possible way from patch to hatchery/nexus/cc.
This is the sole reason why one of them catches up to the other and messes up your stack, because one of them is still adjusting his path a little with each trip, shortening his trip time a little.
Sometimes this shortening of his trip will lead to one of them catching up to the other after 1-3 trips.
A consistent way of avoiding this, is to just line the second worker up with the first (pathwise) and then stack them up, or to stack them once again after 1-3 trips (before he starts moving to another patch), since by then the one that is still adjusting it´s path will be almost on the perfect path already, now you just need to delay his next trip by a slight amount, which you can do by stacking him again.
What you also need to avoid is spam clicking the second worker slowly.
If you click too slowly, you give the worker enough time between clicks to move to the nearest other patch (even if just a little), which means that he will start to adjust his path again with each trip, possibly resulting in another catching up to the other worker in 1-3 trips.
Once they are perfectly lined up (none of the two workers is adjusting their path anymore, they are always using the perfect path) and synchronized, they will never split again, under no circumstances, since they cant catch up to each other.
The only reason one catches up to the other, is because you make one of them start his mining from the side of the patch, thus increasing the length of the path he needs to walk---> then he adjusts that with each trip, shortening his path --> he possibly catches up to the other, wants to go to another patch ---> you click him onto the side of the patch again, which basically means that the stack will fail in another 1-3 trips AGAIN.
Keep this in mind and you will have a perfect stack, forever.
