In my opinion, the answer is revealed anyway, if you have to ask yourself this question at all. As we all know, the intuitive thought is usually right. Therefore, if you have the feeling that something is too close, you should take a closer look or possibly have a second eye look at the situation. However, this does not necessarily mean that you are automatically wrong. "So close is not necessarily too close just because the question is in the room, you may discover that it was if you just take a step back." Source: Two hundred and fifty things architects should know, Michael Sorkin