I believe that Lewis and I would agree that the real point of classical education is not to read Gallic War in the original, nor is it to upstage Latimore's Greek translations.
It is, rather, to learn to think--and then there is a very valid debate over what the place of the ancient languages ought to be. Does it require Latin and/or Greek specifically, or can logic and rhetoric be taught with modern languages?
There are two major reasons that I tend to come down on the side of Latin (and Greek & Hebrew too). The first one is one I haven't totally experienced yet--I'm a Latin neophyte--but I'm told that learning an inflected language is a great way to strengthen one's logic. But even so, Bauer tells us we can do the same by learning modern languages like Russian..
The second, and probably bigger, reason has to do with the adage "He who knows only his own generation remains always a child." Now how does this work with our age of excellent translators? Can't we simply read in translation?
Well, ask the Brothers Bayly about how modern translators treat the Bible and Martin Luther's commentary on Galatians. Take a look at older theological works, where many of the quotes are in the original Greek and Latin. Confused about Newton's Principia or Calvin's Institutes? You might do well to read it in the original.
Confused about the phrasing of Shakespeare, or virtually any older author? Want to understand a legal contract, or virtually any word of significance in the sciences or engineering? Want to learn a modern European language quickly and well? Break out your Latin & Greek--knowing the original makes it easy to memorize the modern cognates.
So is it essential to learn musty, dead languages? No--but it is a short cut to learning the subjects that interest us even today.