I can't but appreciate the analysis you did here, I admire it and I can't but agree with it.
May I add to the work of Capello in a team, or the result of his departure. Because of him not developing any playing strategy or game plan, he tends to destroy the team after his departure. Due to him just adding a block in a previous system, his departure makes this unfit block fall and thus leave a huge gap behind.
After his days at Milan, we all saw how much Milan needed to recover, and it was until Fetih Terim that the team started to regain shape.
Another example is Roma, after being title contenders, they were relgation battlers last year.
Now someone (I don't mean anyone in particular) will tell me that Real Madrid came to win the CL one year after his departure. However, they suffered big time in their league and another thing, he only stayed there one season, so he couldn't cause much damage.
So I get to conclude that Capello is not only an opportunist with a reputation stolen from the work of others, but he also leaves so much crap behind that it takes a while for someone to clean.