Well of course the switch isn't needed if you're a newbie with only one controller. I was just describing my setup. 
Yes - I know

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Last year , was my first year with animated lighting , so everything was new to me. I had problems getting the laptop to talk to one of controllers (I cant remember which one as I had 4 running at the end, it was the first one I tried ) without having either a switch/router in between - this was just when I was testing. So on the ACL forum folks suggested the cross over cable , using a switch , using a router etc etc
Since I ended up buying and using a simple router with 8 ports (and then moved on) , I am curious..