The lyrical delusion is that each of our idiosyncrasies is important. E.g. the rambling, hermetic work of Blake Butler.
The lyrical delusion presumes we have endless time to follow any thought, any digression, any path. E.g. The huge novels of David Foster Wallace.
The lyrical delusion is youthful, vigorous, but not hardened by experience or condensed. The latter has its e.g. in Seamus Heaney and Adrienne Rich.