> My basic conclusion to what you say is, there is no way you can understand classical Latin if you speak modern Italian.

As someone who knows a little latin, spanish and french, I think with a little bit of thought, you can get a decent gloss of quite a bit of classical latin. I'd say it's probably easier to guess at latin than trying to understand italian if you only know spanish.

For example -- the first line of Caesar's commentaries:

"Gallia est omnis divisa in partes tres"

"All of Gaul is divided in three parts"

Spanish (using google translate, because i'm lazy, but you get the idea): 'Toda la Galia está dividida en tres partes' French: Tout de la Gaule est divisée en trois parties Italian: Tutto della Gallia è divisa in tre parti