Spam is never a bad idea.
Had a game last night though that really got me thinking about this again.
I did exactly as you said above, I spammed, and myself and X-Wing wiped the guy between us pretty quickly (he relocated, but he was out of the game from there). Then X-Wing moved on to tag-team Auqia with JBaum, and they got his capital and most of his ships (though it's tough to put Auqia out of the game), while I moved to and stabilized the other front.
The problem was that nobody on our team produced eco, or was ever in a really good spot to do so. Meanwhile, Ferdie filled up the map as he usually does, and started producing out of control eco. By the time I started getting my eco up, we were close to 90 minutes into the game, and Ferdie was the only one with any real income at that point.
Long story short, X-Wing got dumped, and my team called it gg and left. Even without that disconnect, however, we were losing map control, and Ferdie's eco was getting the players we wrecked in the beginning back in the game. At the end of the day, that eco made the difference, and he did it while technically being front-line.