Yeah, I had a quick browse through it.
Yeah, gave it a quick look.
I'd agree with you that generally when your lanes are doing so poorly, you should look to try and help them out. I don't know if ganking would have been that great of an idea in this game, since Zeus doesn't bring a lot to a gank (especially when Luap was so consistently low on mana) and the other lanes contributed so very little too. All the stuns were melee and neither lanes offered the greatest targets.
Honestly, I'd say better lane and mana management would have done a lot more than trying to gank. Viper got his first kill near the six minute mark because he snagged the four minute rune. His next handful of kills were from grabbing the top runes and hitting that awful DK and Void lane. However, Zeus was really winning the lane and there's no good excuse for him not controlling the runes. Had Zeus grabbed those runes, I'm not certain those ganks would have happened.
Second, Luap spent too much time sitting in lane "farming" and not punishing the Viper's absence. He had close to ten minutes to push down Viper's tower since the Viper spent most of that time roaming and whenever he showed up in the mid lane, Zeus just beat him down. He couldn't stay and farm creeps so he farmed heroes instead. If Luap pushed down the mid tower, then he punishes the Radiant team for essentially abandoning the mid lane and also frees himself up to start roaming as well.
Finally, if Luap managed his mana better he could have easily killed the Viper any time he showed up in lane. Farming with Chain Lightning, especially uncontested and when not pushing the tower, is just throwing mana away. Luap never had enough to cast all three of his spells which likely would have brought down Viper any time he showed his face.
So, if Luap bottle crowed and/or controlled the runes I think he could have really prevented the game being so one sided. Get the tower down as well to put some gold in your teammate's pockets and you could make up for the fact that Zeus isn't the best ganker.
Ultimately, Luap was the only one to win his lane but he didn't get anything out of it. I'm not sure ganking would have helped with the other lanes and would have lessened what he'd get in mid so in this circumstance I think he should have just insured that they got the maximum possible benefit from mid that they could. He was one of the highest levels by the time mid game rolled around - and the best farmed on his team - but he couldn't leverage those benefits for anything.