I indeed realised that fightning the minions was not an option, but I new that already from playing single player tourneys. I do not think I touched one of the minions?
The portal locking was what killed us in the end, but that would have been annoying regardless. By that time we had long lost. I was also surprised how extremely unwise it is to fight 2 DGs even for a moment.
but anyways, the minions probably could use some nerving because that enemy Erebus was pretty much untouchable until I finally got him when he seemed to pay little attention for a moment. Giving gold and a LOT of xp for minions that you can actively control makes you think twice about getting minions, so minions is a less favorable option. It would only be fair I think.
EDIT: And btw, I defended our home portals a few times too. 
EDIT2: I opened the game to see what the 'pro's' do so I could learn. The replay hangs at the moment the opposing team's torchbearer drops, meaning that the moment supreme you are talking about is not actually on it.