my pro strat on office ct-side involves the windows
you can shatter the windows without making a break by slashing them with your knife, which makes it hard to see things through them from far away
this is useful because the T's will often not be anywhere as close to the windows as you are
you can then pick up a scout or awp and make a break in the glass somewhere; you'll have the upper hand in reaction time - by the time the enemy manages to figure out which part of the window you're shooting from, you can already kill them