Sometimes there is a reason to mix, when the word in one language doesn't quite match the meaning you want, but in another it does. Like, for example, in Polish "security" and "safety" are the same word ("bezpieczeństwo"), so it would become weird when you're talking about the difference between them.

But I feel like this article is about something else. We don't think in terms of words, we think in terms of phrases, and when we remember those phrases it's not just their literal meaning, but also the context, and this can include the accent they were heard in.

In the ideal world we'd just play the sample that we have in the head, but we don't have that yet.