That's a lie. What is important however is knowing when to do it, when it is worth the time, and when it isn't. Generally, the problem with some 'designers' today is their obsession with tiny things that in reality, don't matter. Maybe its jealousy. One shall look at another map, be awed at how well designed it is, and in order to attack it, criticise how textures aren't aligned - assuming the original designer doesn't know how to align textures properly.
Edges have to be sharp and concise.
You'll never find paving slabs ending halfway into a wall. Pipes use designated pipe textures, nothing else. Cables and supports use textures you'd never see used on anything else. Everything has a single use. That's not the right approach.