The sairs are useful and can buy time vs muta until the goons arrive. If you pump goons then the muta can't do any real damage.
If he goes lurks then the goons will break out in no time, but I'll need obs to exert map control. My FE gives me a short term advantage but I need to push quickly.
Stargate, mass goon and fast robo. No archives. At this point the muta have been repulsed and you're moving out vs lurks. But he's going mass hydra. You need a counter. You need it quickly. You have robo, you quickly throw down a support bay. It's logical. Reavers are a perfect support unit for goons.
Huge Fuck Up
Somewhere along the line your thinking changes. Whereas normally you'd fight hydra with stormers and speedlots you've had a paradigm shift. You know you need to go stormers. You sit there thinking you must. But you've never got the gas because you're always pumping goons and you can't make zealots because somehow you still haven't got zealot speed. And a change occurs. On some level you start to believe if you could just make enough goons it might just work. In your mind you know you need storm, but in your heart you want to believe the goons can do it. You lay down gate after gate, upping it to 9 gates off your main and nat. You take an island. You keep those reavers coming, providing slow but effective support. Nothing can beat you. Goons are like the ultimate unit. 20 damage!!! EXPLOSIVE DAMAGE!!!(fuck yeah!) Kills shit on the ground!! Kills shit in the air!!! Decent range!!! There's nothing dragoons can't take, if you could just build enough of them.
And before you know it you're late game, your grades are 1-1-1, you still haven't researched psi storm and your pure dragoon army is waiting for those reavers to crawl across the map. And that's when the pure hydralisk attack from every side in huge numbers. I lose game after game to this. BackHo demonstrated it flawlessly. I don't know what it is that makes players think pure dragoons are good PvZ. I don't know how we get there. But we do. Even at a pro level players still fall into the trap which gets me over and over. And that is why when I saw sAviOr tear through the huge army of pure goon as BackHo didn't even have an archives 20 minutes into a PvZ I knew I loved him. For me BackHo is hope. I look at him and I think "sure, right now I'm being owned by noobs on ICC because of that basic mistake but if I stick with the goons one day I could be owned by Savior on live television with it".
But there's more to him than pure dragoon PvZ. For shortly afterwards I saw another game of him against sAviOr. And I discovered BackHo has two modes, not one. That's right, not only has he pure dragoon, he has no dragoon.
In game two BackHo did not make any dragoons. Realising his earlier mistake he purposefully avoided them. Early game we had sweeping armies of speedlots. Then we added copious amounts of stormers. By the late game we had speedlots, stormers and archons. The lack of dragoons was so obvious that sAviOr left a overlord following his army and whenever he added an observer he'd cruise a scourge in to kill it. That overlord didn't take a scratch. Every now and then a scourge would be stormed on it's approach to the observer but that was BackHo's only gesture towards anti-air. Time and time again the army of zealots swarmed into the lurkers, then retreated as BackHo realised they weren't very good at that. Over and over they failed to do any noticable damage to ultralisks as he replaced the fallen zealots from 12 gateways. This is a man who doesn't care what his opponent does. He doesn't see the need to react to them, he's got his game plan and he'll do it regardless. Pregame someone toggles him to either Dragoon = 1 or Dragoon = 0 and he'll play it out. He'll push his opponent to the limit with dragoons, or without, but no half measures.
It may seem that this is a weakness, indeed it could be argued that it lost him two games vs sAviOr from relatively strong positions in each. But we should not consider these as losses. Not for BackHo. A loss would be when he goes against his arbitrary rules and makes a functional army. For him victory is the knowledge that he somehow has a progaming contract despite sabotaging his own game.
And one day, when you all least expect it, he'll strike. And he'll use a mixed army and nobody will be able to equal him.
And that, more or less, is why I love BackHo. Oh, and there was that game that Pusan tried to lose over and over but BackHo just wouldn't let him. BackHo plays to nobody's rules but his own. Pusan can sacrifice 9 gateways for no strategic reason, Pusan can throw away as much of his unit production as he likes but if BackHo has decided he's going to lose then he's going to lose and nobody can change that.
Dragoon = 1
Dragoon = 0
Stop fucking up and take the damn win, Pusan!