Even if this were a better approach, all I see it doing is forcing an even bigger torrent of patents into a system already so overloaded that it hardly functions as it is.
How is the patent office going to manage the increase? It's not, the system is going to slow down even further.
This also increases the cost of innovation. If I have a business, invent something, and don't patent it - I'm screwed regardless of if I prove I created it three years prior to the filing. In other words, now you have to file patents for everything to protect your ass (because it's not good enough to be able to prove you invented it first X years ago), and that's a very expensive proposition, particularly for small companies. This encourages the patenting of every little detail possible, even more so than today. Because if you don't patent every little detail, now you will have no right to self defense on the basis that you were the original inventor - they can come after you for every rounded corner you failed to patent, so to speak.
This forces everybody into the patent game.
The rationalizations being offered up, such as that this will be good because it forces openness on innovation are not only wrong (all it actually does it make it easier to steal technology for countries that already don't respect foreign patents), but the negatives are going to far outweigh any supposed benefits.
In five years everybody here is going to be complaining about how they really botched this piece of legislation and how it created more problems than the old system. This will turn out to be an extraordinarily expensive and destructive change; it is not the right approach.