I'll try to write this in order as I viewed the eps rather then just my view on after seeing it all since it changed after watching it all because of revelations.
The episode where Brock gets poisoned was my first but where I really got thinking, On one hand it made sense for Gus to use the one thing standing in the way of killing Walt, Jesse to kill Walt. My complaint with that was it made little sense the way he went about it. As we see through the season with Gus he is clever, plans things out well, this plan of poisoning Brock didn't make sense to me at the time if felt a mistep by the writers.
The plan hinged on Jesse being so blinded by rage that he wouldn't see reason and kill Walt straight away but as we know he didn't, really anyone knowing Jesse would realise that he wouldn't straight away and Walt used reason which apart from like Jesse, Gus getting the Ricen made sense. Why would Walt do it, and now Gus has lost his cook on a plan that had a high probability of failing.
One thing I didn't like was the Gus death scene fell they tried a bit hard to make it seem like he survived, if the toned the injuries down I might have been able to believe since its a show he would make it that far but it was just a bit too much for me to suspend disbelief I think it is.
Then those last few scene I just felt brilliance from them that like Jesse I had been played. Loved it all falling into place and realising that what actually happened made so much sense but the writers did enough to convince and lead me away from it to the path they wanted and to keep me on that path and that was that Gus did it and it was just a bit of poor writing.
Walt was just like Gus, clever, plans things out and over the seasons as gotten better and more comfortable making hard decisions.
And it all made sense as to why Walt would do it in that final scene showing the plant,
- he was loosing Jesse, and that would bring him back to him,
- as I thought to begin with it made no sense for Gus to risk turning Jesse on him,
- someone that knew Jesse would know that he wouldn't pull the trigger straight away just like Walt would know and as such could risk enraging Jesse knowing he could talk him down.
- There was no real way Gus could get or know of the Ricen but this could be overshadowed at the time with other facts
- Walt has no issues putting others at risk in a him or me situation, unsurprisingly of course.
Really enjoyed the ending, good season I enjoyed I its my favourite season ending so far.