I'm so amazed when I watch this video's of high end players. Like how they can micro their units to a tee, but then when the video goes back to their base they have an expansion, defenses, & more production buildings up. I'm interested in how some of these players are able to watch their units & control everything so well. I'd like to watch a replay & just watch it from the terrain perspective to just see what they see, I can also see how they group their units & such also. I sometimes also wonder if they have add-on programs to help.
I highly doubt that they use add-on programs, considering blizzard's policy on cheats, so I would discard that, they use a lot of hotkeys, and have amazing APM.