FBX hat sich auf Gamereplays die Mühe gemacht und einige mögliche Multiplayerstrategien vorgestellt, die als Ziel haben den Gegner möglichst schnell zu stören (Sammler zuerstören etc.)
Der Guide ist auch hübsch bebildert, also falls einer nicht soviel englisch versteht kann er dennoch an den Bildern die Strategien erkennen. ^^Harassment in this guide is used in the sense that your attempting to delay or retard your opponents ability to gather resources or build an effective army.
There are two practical economic goals in the game - booming and strip mining. As you might guess, that means there is a lot of money floating around, and the game might seem to be completely void of harassment. This isn't true, as there is harassment, its just that getting to a point to where you can effectively harass takes some significant investment from that starting $10k. The result is that early game is fairly void of any actual harassment, but is rather a set-up for your strategy as well as scouting to determine what your opponent is attempting to do. Likewise, early game features some significant fighting for strategic points, like buildings that infantry can effectively do damage in, as well as preventing hard rushes.