Something on World Trade Center 7

• Why did this mega-smart/mega-dumb conspirators not pull the building at 3pm? Surely waiting until 5.32pm would be far more suspicious.*
• How did the mega-smart/mega-dumb conspirators know that part of the WTC1&2 would fall on WTC7? They couldn't just demolish it without it having sustained some structural damage or it would be obvious that they demolished it!
  

*WTC7 was empty from ~2.30pm onwards.