Earlier quoted context omitted.
I'm not disputing that efficient code can be easier to understand in some instances, just that the assertion that efficient code is easier to understand. Logically, disputing that just requires a single instance of efficient code that is hard to understand. I think that's a trivial enough example to be self evident. In reality, I'm just wondering what they were trying to convey with that statement. I doubt they would…
Fair point. It's possible when they said "efficient", they did not mean "hardware efficient, runs fast, doesn't use a lot of resources" but "developer efficient, faster to write and easier to understand". But that entire phrase as is doesn't make sense, I agree with that. It's also possible to be a simple mistake. Maybe they went overboard with marketing phrases and claimed something that isn't quite true.
Unfortunately, if it is just poor communication on their part, we'll likely get no answers that can be considered more likely than others without original author or someone related (work-wise) piping up.