Mavericks does not remove USB sync of iOS devices.
What he is probably referring to is that the latest version of iTunes removes USB sync of contacts and calendar data. The next version of iTunes is rumored to restore this functionality.
Well, isn't that intriguing! Everything I had read--or mis-read-- indicated it was Mavericks that had stopped the UBS synching and was requiring wi-fi.
Uh-oh! Just remembered that I upgraded iTunes the other day. Yep, it's now the latest version 11.1.5 (came out in February). Let me test your statement.
I entered an event in my iPhone and one on my calendar. Just synched via USB cable. Now checking on the calendars on both.
Guess what? Even before I could finish checking and type up my reply, an alert popped up on my Mac from the event I had entered on my iPhone. When I looked at the calendars on both, they each had the other's new event.
So, you are WRONG!! The events synched both ways--via USB cable.
So, indeed, it must be Mavericks that is requiring the wi-fi synching!
Hope you can clarify...