Not sure if it was in the WL7 manual, but this is from WL8:
The audio signal flow goes through the various sections of WaveLab in a certain way.
• Read audio clip samples
• Clip envelope (unless post-effects mode is active)
• Clip effects
• Clip envelope (if post-effects mode is active)
• Clip pan
• Clip individual gain (Clips window)
• Clips are mixed into the track slot (for example, overlapping clips)
• Track effects
• Track leveling/surround pan
• Each track is mixed into a bus that has as many channels as defined by the Audio montage properties (between 1 to 8, usually 2).
• These audio channels are processed through the plug-ins of the master output.
• These channels are then sent to the Master Section input.
Master Section:
• Channels/sample rate might change at each plug-in slot
• Master Section meters
• Master Section Dithering slot
• Independent meters
• Playback or file format rendering