I think you are just reading too much into some colloquial English. If I say that "Aunt Elsie coming to dinner means trouble", I don't literally mean that "Aunt

I think you are just reading too much into some colloquial English. If I say that "Aunt Elsie coming to dinner means trouble", I don't literally mean that "Aunt Elsie coming for dinner" is a synonym for any kind of trouble. It is clear just from the context of the sentence you quoted that this non-literal meaning is intended, since "difficult to analyse" is very obviously not a mathematical definition. And in case this was not clear to anyone - which I already find surprising - they inserted the word "basically" which is another colloquialism that can mean "not literally" (depending on the context).