Quoted for Truth. When we were getting stomped in WvW, I asked /team for volunteers to form a raiding party just to harass supply camps. No objective other than to sweep in, take the camp, and rush to another one.
Not only did we have a LOT more fun and generate a lot more Karma / XP / Gold, but while we were doing it we also scouted locations for a larger group that was roaming about doing the same thing to towers. I can't say we were totally responsible, but while doing this the towers we had fought for didn't come down the entire time. I think the hit-and-run tactics, being an invisible force of aggression, may have pulled attackers from the front, thinking that there was a huge zerg moving around when, in fact, it was never more than 5 guys.
We also helped to throw up a LOT of siege equipment, because we were constantly capturing supply points, we always had some to spend, and it didn't affect anything because 6 minutes later we'd be across the map raiding another camp for more.
I think a quick, organized team, capable of seemingly-random strikes from anywhere (we used the lake for cover so much we were probably impossible to track) can really throw off an aggressive team. A couple working in tandem, dumping supply off where a larger group is setting up siege, could be lethal.
And we were all melee too, if I recall.