What rating separates the experts from the lesser skilled players?

When does someone get the innate feeling that they have reach a close to expert understanding of chess?  I'd say when one reaches the ranking of about 1600.  To reach this ranking I believe one has to invest not only considerable time, but also money.  I am not convinced that reading and training, as well as online play will do the trick.  Most likely, one has to participate in over-the-board play and travel.  I think a certain staleness can result from internet and local club play.  Now don't get me wrong I very much enjoy every aspect of chess!  I'm just speculating as to what it takes to really improve one's game.  I am very uncertain as to whether or not I will ever reach 1600.  However, hope springs eternal!

Good luck to all!