I guess it'll take some time for me to get used to the flashbacks. I understand why the writers chose to gradually explore what happened during the past year, but I think I still would have preferred it if we had gotten to see these events in the right chronological order. Sam & Dean have never been apart for more than one, maybe two episodes, so seeing them being on their own for half a season or so could have been really interesting, IMO.

I thought they were a nice touch ! but it really would have been interesting to see how they deal with things on their own for a change

By telling it in flashbacks, it adds another layer to the story. We don't really know what happened to these guys during that year and therefore why they're reacting the way they are. I much prefer it this way because it adds suspense and mystery to the story. Linear story telling can be boring, I like it when they spice it up.

^ I agree. And the idea of making it in their point of view also adds on to the storytelling. I love how perspective is seen in the flashbacks. Plus, it keeps the story going easily. The whole sparse truth of what the boys did that year shown in one episode would start to get dull. I also like the fact that their flashbacks are shown when one of them sees something familiar, reminding them of what happened.
It's Sam and Dean telling their side of the story :)

"Where's the angel?
Perfect.