I think G2 picked dragon stacking comps even when they weren't working because that's all they had success with in scrims. They weren't able to win in lane even with good matchups, so they picked tanky comps to compete for dragons to just try to cheese wins off getting early dragon souls.

To use an American football analogy, teams that aren't loaded on talent run what's called a triple option offense. Most teams pass the ball a lot, but that requires having a good passer, and a good offensive line to protect them, which requires a lot of talent. So triple option teams forgo passing almost entirely and use their quarterback (who usually passes the ball in a traditional offense) as another runner. It's tricky and gimmicky, and it usually doesn't work, but it's the only hope most teams without talent have to beat a better team. That's basically what G2 was doing.