The world is full of many talented men who can step into every demanding job out there. What i find often missing is that oddity called fine judgement. That is surely Comey's flaw and as surely the flaw that made Hilary a marked woman however talented. Yes his job was impossible and surely it was in the nature of the Obama White house to politically compromise all potential threats which he certainly represented.
In the end, his abandonment of the Email fiasco instead of kicking it upstairs where it belonged was bad. Yet it may have been forced. And then he should have resigned.
Then we have the untimely change of heart just before the election. There was a way around a public airing in this case as well.
In the meantime he is riding herd on a host of serious investigations that beg visible activity as well. So Why?
I also do think that Trump wants action and that Comey is a master stonewaller or likely appears to be. That is not something that Trump could tolerate forever.
In the event, this parting was inevitable and necessary and still regrettable..