I realise you may already be familiar, but I figured it'd be worth expanding a little for other readers.
What he was talking about is the DP, the "Dragon Punch", also known as Shoryuken, that Ryu / Ken are famous for in Street Fighter.
The mindgame is that Shoryuken is 100% invincible: no matter what your opponent is doing, the Shoryuken / Dragon Punch will have infinite "priority" so to speak, it punches through all of your opponent's options because your hurtbox completely disappears during the move. That's right, your hurtbox is not merely "shifted", its gone. You're fully invincible.
Of course, for balancing purposes, the Shoryuken has high-cooldown and high-periods of counter-hit status. Which means that although the Shoryuken "beats" all other attacks in the game, it also loses to a simple block into counter-hit.
-------
So the mind game becomes one of timing. You approach the opponent, making them _THINK_ you're about to throw out an attack. They dragon-punch in response to your movement. But instead of attacking, you just block, and bam. You beat a player who spams dragon punch.
Because of this extremely heavy "Dragon Punch wins vs all attacks" mindgame, there's a rich strategy / dance involved called footsies where the two players try to get each other to push the attack button first (especially if in a mirror match, Ryu vs Ryu or Ken vs Ken). The 2nd one to attack wins, because of the strange property of invincibility.
----
As far as Fighting Games go, the "Shoryuken" / Dragon punch is most similar to this "hard counter" found in RTS games. Shoryuken "hard counters" all other attacks in the game.
While "simply holding the blocking button" consistently beats Shoryuken. Its a hard counter, always going to win if and only if you know exactly what the opponent will do.
Because these options require understanding your opponent's mindset (when / timing of their use of Dragon Punches and/or blocking), they lead to incredibly fun mindgames.
Also people cannot SRK/DP on reaction to all attacks or the game would be completely broken so saying '2nd to attack wins' is a bit odd since it's only in the situation where both players use an invincible move.
In StarCraft 2 if your opponent builds one unit there's another unit that hard counters it but you rarely bring just one kind of unit into battle last the very early game. Early zerglings are countered by marines are countered by hellions are countered by roaches are countered by marauders are countered by flying mutalisks are countered by marines again...etc etc.
If you bring marines and marauders and some hellons with healing medivacs it becomes about numbers and engagement positions. Sometimes you have no chance of winning but you have a chance of getting an economical trade that will put you in a better position in the future - without the trade the next fight your opponent might have too many units for you to win.
I guess it depends on what game you're playing but in RTS there's the fight you're in, the economy, production,upgrades, as well as the overall balance of the current game that all can change the way the game is going.
You have to play red alert to really know what the author is talking about. 50 riflemen probably loses to one flametank in command and conquer. Even the Immortal doesn't stand up to such odds and/or resource advantage. The flame tank isn't a capital ship either (not a battlecruiser or a mammoth tank in C&C world), it's just an anti-infantry tank that is highly effective at it's role.
That is, I'm pretty sure 50 Roaches beat one Immortal. And that's the closest thing to a hard counter I've seen from the StarCraft world.
Dark Templar vs anything on the ground without detection? Burrowed investors against anything without detection?
The "Stealth vs Detection" thing isn't quite the same. When you have a mixed-army (ex: Light Tanks + Flame Tanks) go up against another mixed army (ex: Riflemen + Rocket Launchers), the "Hard Counter" remains in fact, a hard counter.
No amount of "support" will allow those Riflemen to damage the Flametank in any reasonable manner. (And Light Tanks may not be able to damage Riflemen, but Riflemen can't damage Light tanks either). The few rocket soldiers you have allow some degree of DPS, but its just a matchup destined to lose no matter the support you put into the mix. In all situations in all manners of various support and/or mixed army compositions, the Riflemen will be useless against Flame Tanks.
Riflemen don't do much damage (maybe 1HP??) to Flame Tanks. Riflemen are slower than Flame Tanks, while Flame Tanks one-shot Riflemen with a large area-of-effect damage. Flame Tanks also kill Riflemen by movement (if you move into a squad of Riflemen, they all get squished before the flames even come out). The Riflemen have to constantly micro away from the Tank's movement to remain alive.
Effectively: imagine if those Colossus in SC2 had armor that only took 1-dmg from Marines, had special code to "step" on Marines to kill them (aka: instant-kill any marines that are under the Colossus), and had a movement speed roughly 2.5x faster than Marines. Also imagine that Marines didn't have stimpacks. Colossus retain the area-of-effect lasers, except the lasers one-shot marines. And you're beginning to see how hopeless Flametank vs Riflemen look like in C&C.
--------
In contrast, 12 Zealots will probably beat 12 Dark Templar (or roughly go even there-abouts) as long as detection is nearby. Its a very different mechanic from the C&C-style "Hard Counter".
A "Hard Counter" remains a counter, even in the presence of supporting units.
--------
Starcraft 1 / Starcraft 2 just aren't as "counter-heavy" as other RTS games. In Age of Empires: Scouts lose vs Pikemen. Archers lose against Scouts. Castles lose to Trebuchets.
Age of Empires 2 isn't as "hard counter" as C&C, but its closer to the spirit of C&C's hard counters than anything in the Starcraft / Starcraft 2 world.
Case in point: A 4800 HP Castle shoots 4-arrows of 11-damage against 35-HP Crossbowmen who shoot only 1-arrow of 1-damage back in the same time period. (The 8-damage a Crossbow normally deals is turned into only 1-damage vs stone-structures like Castles or Walls) The Castle "Hard Counters" Archers. There's no composition where an archer would ever be useful at anti-Castle warfare in Age of Empires 2.
(Castles don't truly "counter" Archers however, because Castles can't move. Within the scope of mobile armies, various units get random bonuses against each other however, which plays somewhere in between SC2's soft-counter style vs C&C's hard-counter style. Nonetheless, strong players will bring 20 villagers to combat if only to build a castle during a fight, because of the ability for a "pop-up Castle" to beat so many different kinds of units. Especially in the Castle Age... the "Hard Counters" for Castles is locked away in Imperial Age (Trebuchets and/or Bombard Cannons))
Consider speed-UNupgraded Zealots vs stutter-stepped Vultures !
Zealots have a clear advantage in terms of HP an (most likely) DPS, and yet they lose badly...
Flametanks have pretty much every advantage over riflemen:
* Cost in terms of combat efficiency: one flametank can take out multiple dozens of riflemen.
* Flametanks have more speed.
* Flametanks require less micro / APM. To keep riflemen alive vs Flametanks, you need to constantly micro-them outside of the Flametank's movement (by default, riflemen sit still and shoot their rifles. As the flametank approaches, they get run over and instant-killed before the flametank even fires a shot).
APM-advantage, Movement advantage, cost-efficiency, DPS, armor. Everything. Everything about the Flame Tank beats Riflemen on every aspect you can possibly imagine.