I know this thread is kind of dead but I thought the people here would be better at games than they are. If you play a game at more than a casual level you play a different game. Playing an RTS vs AI is useless and easy. If you reference any strategy to playing an AI its void because the AI in RTS are absolutely horrible. Only by playing a human opponent, who is also skilled do you play the real game. If you are playing an AI you can do almost anything and win, which is why most single player games need story to not suck. There may be 100 strategies vs an AI but only 50 versus a casual human. Versus a skilled human you may have 10, and I'm talking about someone who plays the game to win. In fact if you lose a few workers in starcraft, a key dropship gets shotdown, a pylon powering your gateways goes down, or some speedlings run into your worker line because your zealots left your choke for 3 seconds YOU LOSE. The professional players play at up to 400 APM, which is actions per minute. That is insane and is 6+ actions every second. I currently play at around 100APM average and spike to near 200 in micro battles, and its very intense. You are building, teching, mining, scouting, and the whole game is extremely fast paced after the first minute. At my skill level, which isn't even high, the awareness factor is way more than any other game I have played and I love it. Multiplayer RTS requires such skill, awareness, and precision it is unlike any other game. Go watch a starcraft pro playing from first person and you'll see how lightning fast they are and how they switch camera to multiple spots and multi-task like nothing else in gaming.
If one key unit dies or something is just slightly out of place it will be abused. One small error can end a game in an instant, although this games can last a long time (up to 45min). Things such as turtling don't exist because it doesn't work. Sure some matchups like Terran mirrors are more tank defense wars but it is NOT turtling as they actively expand and rely on units rather than defensive structures because a few too many defenses and their units will be too small to hold. That is RTS. Having turtling being a viable strat will never work in a good RTS because defenses that auto attack and require little thought once placed are the antithesis to RTS multi-tasking and awareness.
If you do not play an RTS online with people at least 4 hours a week and try to get better you aren't even playing the same game. And if you do spend a lot of time and are turtling you are either lucky, terrible, or all the bads who die turtling in Starcraft moved to those games.
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"He who defends everywhere, defends nowhere" - Art of War
And if you turtle you defend only a small area and will run out of resources. The immobility of defensive structures versus an armies ability to be defensive, offensive, harass, contain, etc is what makes turtling not viable. In real war supply roads will get cut as well so you will starve while they take the rest of your land unless your lucky enough to have severe terrain advantage around your entire nation, aka Britain. But the Nazis made rockets that could bomb England from Germany. And the Japanese bombed Pearl Harbor. America bombed Japan. And even the Greek Spartans eventually lost because of the Persians macro.
I was reading some old battles and there was a city on a hill and the army built a ramp and got in! Alexander the great made an island a peninsula and his siege towers went right up to the wall! Defense are to DELAY and DETER not to stop an army. Its like this in RL and games, except in games it would be stupid to have both sides sit in castles for a long time while they starve or spend hours to beat something that took zero skill and effort to do. If you like defense play a defense game or custom maps, real RTS is about offense and insane multi-tasking/awareness.