I read this long ago when I took a class on this dialogue with the author at Catholic University's School of Philosophy.
I know I found both impressive (it was probably annoyingly obvious I had a little crush - I always get a crush on anyone, of either sex, who is half way presentable who loves classical political philosophy (perhaps I need a throuple as a symposium?).
Sadly I remember little, other than I think the Phaedrus further explored the image if the tripartite soul (a throuple of its own!). Before the curtain falls, maybe I can get into a Catherine Project class on this dialogue. If so I hope to see you there Goodreader
Anyway Dr. Griswold is great and you should read his other books. I may myself.