Starcraft – What are the benefits of rallying all workers to the left or right-most mineral node

I would argue that if you're just starting out, grid hotkeys are more efficient since you can memorize either which key it is or where on the unit-card the button is located (visual cues tend to help memorization) - and if you don't know the hotkey, you can find it without mousing over the button.
Also, all the keys are on one side of the keyboard, meaning you won't have to move your hand as much.

That being said, the vast majority of players use the default keys either because
A) They don't know grid exists, or
B) They are already used to the default layout (grid was not an option in the beta), and/or were already used to the very similar layout of Starcraft 1; there really is no benefit to them learning a new layout if they already have the default hotkeys memorized. Most competitive players would fall into this category.

So I'm not going to lie, you lost that game because you mis-clicked half your army into a dropship in the middle of the final battle and it got shot down almost immediately. I assume you weren't trying to give yourself a handicap there, so let's ignore that and focus on the rest of the game.

Let's focus on why your macro is so bad.

To help you understand why its so bad its important to understand what Macro is:

Macro as a gaming technique is an application of economic theory; at its simplest it’s a distribution of limited resources between necessary avenues. Consider the simplest example from Starcraft: I have 50 minerals, I can purchase another worker to make minerals for me, or I can build an attack unit and go kill my opponent. The implied choice here is that I can trade an economic advantage (having and making minerals) for a tactical one (having units). Since winning usually requires a tactical advantage, at some point a player must make the decision: I’m going to sacrifice my economic advantage for a tactical one. To the uninitiated this may seem like an easy choice: I’ll just build attack units and destroy him if he’s building his economy. However, this sort of theory crafting doesn’t hold up. Once you consider things like: distance, time to kill, etc, you quickly realize that the person with the larger economic advantage can produce a larger army. How far away, and how long it takes to build an army are important factors in deciding between tactical vs economic advantage.

Now if every decision you make is the difference between an economic and tactical advantage (I'm going to ignore teching for a moment), then we can further provide analysis by saying: Unused tactical advantages are worth less.

In your replay you open up with 1:1:1 and transition into nothing... Or, maybe it's more accurate to say, you build everything. Here is a list of what you build (at the 9 minute mark):

• 2 Barracks (one with Techlab)
• 1 Factory (with Techlab)
• 1 Starport (with Reactor)
• Engineering Bay
• 1 Siege Tank
• 12 Marines
• 5 Vikings
• 1 Marauder

At this point the only thing producing units is the Starport. Out of all these units the only thing you actually use is those 5 Vikings, of which you lose 3 in exchange for 5 probes. Your problem is that you built a bunch of stuff and then just kind of let it collect dust.

Imagine if I built a Refinery and then didn't put units in it for a minute. It would sit idle. Those 75 minerals I used to build the Refinery could have built another Worker, he could have worked for the minute, produced just as much minerals as I spent on him, and I'd still be able to afford the refinery when I needed it.

• The first rule of Macro is: build a lot of stuff
• The second rule of Macro is: don't build stuff you don't need

You're building stuff you don't need. You build your Factory early on and even give it a tech lab, and then it sits idle for 10 minutes. The sole Tank you build out of it in those 10 minutes also sits idle. You build two Barracks, but only produce a handful of units and then let it sit idle. You're not building stuff as part of some larger game plan, there is no timing attack you're waiting on, you're just building stuff to build it. At one point you even build 2 Turrets, despite the fact that you've never scouted a single Starport (and you already have air dominance through Vikings).

Now I understand why you do this, its because the Starcraft single player teaches you to be a bad player. What the single player does is teach you to build up your defenses. Trench in, and wait until you have a massive force with which you can move out and win.

Have you ever seen Boxer "trench in"? Ever seen TLO (NostraDario, the BC rusher himself) build unit producers and just leave them idle for 10 minutes? You know why you don't? because its waste of resources and very bad macro.

Let's take an alternate reality for a second. In this alternate reality let us pretend there is an evil Carlo, who hates his opponent to death and wants nothing more than to kill him.

This Evil Carlo opens up Reapers! Why? because he hates his opponent and Reapers are awesome early game against Protoss. Does he stick his Reapers behind a wall in? No, he rallies them directly to his opponent's mineral line! But his opponent fights off the Reapers with Stalkers, so Evil Carlo starts building Marauders and Hellions! That's right, rallied right to his opponent's choke GASP. And the Marauders fight off the Stalkers while the Hellions slip into the mineral line and toast Probes. Why? Because Evil Carlo hates Probes. He hates Probes with a fiery passion which consumes him to the point of rage. If he saw a Probe get hit by a bus in the middle of the street, he'd run over to it and start kicking it in that one big eye Probes have. Unfortunately, the Marauders can't hold out against the 4 Warpgate Protoss and Evil Carlo is forced to back off. But never fear, he's already built a Starport, but instead of swapping for the Reactor he swaps for the techlab! That's right Banshees. Evil Carlo is snarling with hatred and anger for his opponent so he produces Banshees which force the Stalkers to run around the base like chickens with their heads cut off. Evil Carlo laughs at the foolish Stalkers MWAHAAHAHAHAHA. But meanwhile he's started producing Siege Tanks and Marines (having swapped add-ons), and as soon as the Banshees die he's moving out with Marine/Tank, which he Sieges in his opponents natural! His opponent hunkers down inside his base, desperately trying to build Immortals. But what's this? Evil Carlo has started producing Vikings. The Vikings fly over the Marine/Tank force providing sight to his range eight billion Siege Tanks. Evil Carlos' opponent is at a loss for what to do, so he blinks his Stalkers into the middle of the Siege Tanks, only to learn that Evil Carlo's Marines are stimmed! AH THAT'S THE STUFF.

Evil Carlo sounds like quite the player doesn't he? Here is the big difference between Evil Carlo and real Carlo. Evil Carlo attacked his opponent with every unit he had. He constantly put pressure on his opponent and drove his opponent to make poor choices. Now obviously, if you blindly rally your troops into the enemy base you're not going to have this kind of success, but I'm trying to emphasize a point here: USE YOUR STUFF. Every building I mentioned in that story you built. You could have had that army.

If you're not using it, its kind of a waste. Yes, you need to "build an army," but no one's saying you can't use that army while you're building it.

USE IT