In my opinion, Ken Jennings has done a good job in what we all know is a position that very few, if any, would be comfortable in.
As for:
” In one episode, a clue looked for a response of “Dr. No,” the famous James Bond villain. When the contestant gave the intended response, Jennings followed up with “No — that’s correct.” The host’s seemingly oxymoronic “ruling” prompted quizzical looks from the contestants, and what may have been a tape stoppage to sort out the confusion. Other episodes appeared to suggest tape stoppages as well, although these could have arisen from factors outside Jennings’s control — checking the accuracy of a contestant’s response, for instance.
I don't think Alex would have handled that response much different than Ken.
With the tremendous pressure involved in taking over for Alex Trebek yes, there will be confusion and tape stoppages. I doubt Ken Jennings will fill the spot permanently however, until they find that host, cut the man some slack.