Here is the situation:
At C90 all of the departures are cleared to their destination via radar vectors to the first fix. To the east and south, we have RNAV fixes that the aircraft are sent direct to before being shipped to the center and after we are done vectoring for spacing, past the arrivals, weather, etc... My question is are you supposed to say Proceed direct (fix) or Cleared direct (fix) or is there no difference. I have heard both used, but that doesn't mean it is technically right. I try to use Proceed direct (fix), as that was how I was trained. I think that for the most part using either one is not confusing to the pilots, but are you technically changing the clearance limit of the aircraft by saying cleared direct? Thanks for the help.