Thank you Steven!
Yes I will try and see what I can come up with. And really really very helpful you took the time to post a screenshot of your export settings. And also changing to CBR for maintaining as much as the original as possible, I would not have thought of my self..... So I am trying now some exporting with some of my clips, and comparing @200%. At least I am already shooting with the All_I intraframe compression, but thanks again to all the answers, I learned a lot more, and understand now also how this would really be something of a holy-grail in postproduction. But then, also, how I found out now, for some codecs this does already exist in Premiere Pro. It is explained here in the link given by Mark Mapes: http://blogs.adobe.com/kevinmonahan/2012/10/11/smart-rendering-in-premiere-pro-cs6-6-0-1-a nd-later/. So it seems that if you are shooting and editing with the right codecs, simply cutting and exporting from the same clip is actually possible. Only the Canon EOS 5D codec is not supported for this feature of smart rendering in Premiere Pro!
Too bad, but again learned a lot.