This may come as a shock to some, but Barghouti's opinion is his opinion, and not some authoritative definition when it comes to Right of Return....
The subject of right of return isn't a simple one, as there's been a lot written on it and most who support it do believe there can't be an unrestricted return of refugees because as you hinted at in one post, that would be a having the cake and eating it too sort of thing. During the Oslo era the PA formally accepted a negotiated resolution of the conflict and in doing so recognised there couldn't be an unrestricted right of return. Right of return is going to be a symbolic thing which will satisfy all parties that UN resolution 194 has been complied with, and will be made up of return of some refugees, compensation for others, and resettlement in other countries. This is a very reasonable sort of thing to wish to achieve, and it's why I strongly support the right of return.
Here's one really good publication about it and I hope you do read it as some of it's very interesting and goes into detail about the refugee quetion and right of return...
Palestinian Refugees and the Politics of PeacemakingI'd also recommend a book called 'Palestinian refugees: mythology, identity, and the search for peace' by Robert Bowker, though it's a bit of a dry read and speaks more about the sense of identity of refugees. The book might be hard to find and expensive, but I found a huge chunk of it online, so you should have a read if only to have a laugh at me for paying over $80 for it back when I was studying and long before it was available online like this...
http://books.google.com.au/books?id=LOYtfyJFBIQC&printsec=frontcover&dq=Palestinian+refugees:+myth+bowker&source=bl&ots=wHm8yV-NUn&sig=sPb4sa4VCpbNbxnaf9CkWOwtITk&hl=en&ei=tr-RS4CIFY_40wTW2dzkDA&sa=X&oi=book_result&ct=result&resnum=1&ved=0CAYQ6AEwAA#v=onepage&q=Palestinian%20refugees%3A%20myth%20bowker&f=false