Truth is, none of us will know anything about the ins and outs of the contracts - if he had similar break clauses in previous incarnations of it, if either Vettel or Alonso were unwilling to drive with each other, or what. If Ferrari were shopping around for a distinct reliable number 2 as long as Alonso was laying golden eggs and they wanted to keep him happy, then they definitely weren't looking at Vettel until Alonso exited stage right.
Having said that, for fulfilling a childhood dream, will take any opportunity to drive in red blah blah blah he's picked a shrewd time to do it (which isn't to say I don't think it's a childhood dream, I just think that sometimes dreams and practicality had to meet.)
Absolutely.
Vettel is my favorite driver on the grid. Before this year I might even have argued that he was the best driver on the grid. I am not a fan of Alonso. So much so that I have not cared for Ferrari (my favorite team ever since I started following F1 from before most of you were born) since he joined. He's just too sneaky for my taste. But I can admit that as a driver he is very, very good. After this past year, I would rate him as second best, behind Hamilton. The latter bested him head to head as a rookie, so to my mind there is no question there. I'm not a Hamilton fan either. Now Ricciardo may be the equal or better than one or both of those two, but we really have to wait to make that determination.
So, right now, Vettel is at best #4 by my reckoning. Unless Ricciardo proves to be so good that he would have shaded the other two also.
So, absolutely, you are so right: Dream and opportunity coincided in this case. And that is so fortunate for Vettel. I have serious doubts that he would have been able to realise his childhood dream, if the opportunity had not presented itself right now. The manner in which Ricciardo so comprehensively outclassed him, raises serious doubt that he would not have suffered the same fate again in 2015. Pride would have prevented Ferrari from hiring a clear #2, IMO. And they would have had other options to hire an ascending talent rather than one in decline, as Vettel would have been percieved to be. Now one can argue that his problems were an aberration. Weak IMO but with a slight chance of being plausible.
For my part, I am so, so delighted. My favorite driver in my once again favorite team. I can only pray that he and future events will conspire to remove the smudge on his record that this season has been for him.