Influence and social engineering are two completely different things. I don't know of an example of a person being compelled to do a very specific task or divulge secrets based on reading a poem. Do you?
compelled as feeling obliged to do something that before they heard the poem they were not particularly keen on doing? obviously not, this is why the phrase "patriotic rhetoric" which I have just invented did never exist in this world nor move men's hearts into battle despite their better judgements.
if you mean compelled as forced then no, but then most of what we consider social engineering wouldn't be either.
sorry but I mean there are parts of Shakespeare that historically if you quoted them at the right moment you could make a lot of English people lay down their lives, if you think that is just influence, well ok then, I guess I would say social engineering is a weak thing and it is influence that one should practice.
on edit: if you mean social engineer as in just get a human to give you info to compromise a computer system, well yes, but then I would just say, gosh the decades in which it has been possible to socially engineer humans to compromise computer systems are ones that have seen a great decrease in the power of poetry to move people's hearts. Even so I'm sure someone could still recite the right verse of Russian verse to get some specifically susceptible people to crack.
I think they mean just in general and historically. Both can be used and work together.
Imagine some handsome travelling gentleman (who's actually a soldier) woos a local bar maiden with some fancy words and poetry. Oh wow he's so educated and dreamy~! Then he proceeds to chat with her and gets her to divulge a bunch of info about local troops movements she has seen and etc.
That's my take on it at least.