I have not been into RTS or 4x since Warcraft 3 and/or Civ 3, so I'm way out of the loop on things.
This game is phenominal.
Presently, as I'm learning the game and relearning the genre(s) I need to slow things down.

I was wondering what the "Game Speed" slider affects. 
I switched from normal to slow, and have don't see a change in build and travel speeds (which is fine).
Is the change "under the hood"?  What is altered?

I'm playing SP 1v1, by the way.