> Search relevance is incredible difficult, especially when there is not enough information provided in the query and there are multiple "correct" answers. Someone is always going to be disappointed.
Sure, but in that case you go with the answer that will be the correct answer for the most users. Which in the example in TFA would almost certainly be London in the United Kingdom, not some other London in Kentucky or Canada or what have you. You'll end up disappointing those users who actually want to know the time in those Londons, but there are going to be a lot fewer of those.