The big difference between genuine reading and coding is the variability of scanning / focus. When you read, you usually want to take it all in -- it wouldn't make sense to jump around because it's a single, linear journey.
Code does not observe this rule, so the more experience you get as a coder, the better scanner you become. You quickly view a class and think "ah yes yes.. it's _roughly_ doing this.. that" -- you sure as heck don't read the whole thing carefully word by word! The best coders are amazing scanners -- capable of pointing out a missing parenthesis in a sea of parenthesis. This argument against syntax highlighting is like taking the batteries outta our flashlight. Sure, we'd be more careful but our productivity would surely suffer.