When filler words like um and uh and er rise in frequency, it can be a sign that something difficult is being talked about. (Er-cancer was the ur-cancer, etc.). But words like um and uh and er are fairly uncommon in difficult poetry.
If this just indicates that two different types of difficulty are involved, what does the specific disanalogy say about what they actually are? Or if not, why do few difficult poems contain fillers?
Where do fillers normally appear? Firstly, more or less corralled in their proper language. In Portuguese, é and hum are common. Also. (1) The usual uh purpose of fillers is to “hold on” to the speaker’s “turn” (see note A) – to indicate that they intend to carry on talking (in my case, forever), although at the moment the filler rolls out, the speaker presumably isn’t quite ready to continue. (2) Provoking that very presumption – with or without real intent to fool the audience – can be a kind of ancillary purpose of fillers. In other words, the speaker might say “um” not because they need a moment to think, but because they want to mark what follows as that which uh characteristically would have been preceded by a moment’s thought. Such heralded utterances are often especially apt (because chosen with care) and/or especially inapt (because chosen as a compromise, what feels like a next best option). (See notes B, C & D).
Note A: Holding on to the speaker’s turn – it’s worth mentioning that some fillers slip into speech which would otherwise sound pauselessly fluent. This might indicate an especially firm grip on the turn. I can also imagine it indicating language which is only very slightly behind schedule. “We’re expecting the verb any – in fact here she is now! May I present: reshoogle.”
Note B: A next best option. The unavailability of the implied better option is unavoidable in various degrees and with various presumptions.
Note C: Some speakers, BTW, may sharply differentiate for long periods between, for instance, “um” and “uh.” In an example I noticed, “um” was much more emphatically indexed to inclusion of the listener’s (as it happened in this guy’s eyes totally fucking preposterous) expectations; “uh” evidenced personal semantic struggle.
Note D: and/or inapt. The filler may be in league with an ensuing ardently apt / half-heartedly inapt tone. But to me the more interesting case is when it is not: then it’s like the aptness spectrum has swollen, without ceteris paribus a spot having been selected along it.