This really isn't worth arguing over.
Yes, it is a misspelling but, it gets the point across.
If I saw the word, "synoptic" I would think it had something to do with eyesight (optic)
Whereas I know "syntopic" because it has the the word "topic" in it. 
I used to be urked by misspellings in books, too (English Minor). But hey, I figure lifes to short to "cross every 'T' and dot every 'I'
Jonah
