question about spectral pitch display

Its primary purpose (if you zoom in on it) is to help you to identify individual components in your sound, in a way that you can't easily do on the frequency display. Also, it displays this information on the timeline, unlike the spectral frequency display, which only gives you an instantaneous time snapshot, or an aggregated one if you scan a whole section.

So whilst the frequency display is much more use for showing you the overall 'shape' of your sound - the relative amounts of bass and treble, etc, the spectral pitch display, being aligned with the waveform, will make the duration of individual sounds much clearer. And of course, because you can make spectral selections on it, you have a lot more flexibility in what you can cut out. It's also really easy to copy just a part of the spectrum from one place and paste it to another - which can sometimes be more useful than you might think. Also, you can make much more accurate spectral selections to apply Auto Heal to, so you don't remove more than you need. It's a bit old now and uses a previous version of Audition (3, where you accessed it differently), but there's a good video about some of the stuff you can do with it from Jason Levine - Noise/Hum Removal in Adobe Audition 3 on Vimeo.

Once you get used to what you can do with it, you'll wonder how you ever managed without it!