In the new JSNT T.J. Lang argues that there are two kinds of "seeing" in this verse. The upshot is a fresh and convincing read of the passage as a whole. From the abstract:
This article argues for a reading of Lk. 17.22 as antanaclasis, which is a form of rhetorical wordplay in which the same (or a similar) term is repeated, but in two different senses. According to this reading, Jesus introduces his discourse to the disciples (vv. 22-37) with the prediction that in the coming days they will desire to ‘see’ (as in witness) one of the days of the Son of Man but they will not ‘see’ (as in comprehend) these days when they occur among them so long as they fail to understand that suffering is primary to the Son of Man’s identity. Such a reading coheres with the larger Lukan theme of the blindness of the disciples to the necessity of Jesus’ passion. Such a reading also requires a rethinking of the assumption that the subject of Jesus’ discourse in 17.22-37 is the parousia.
The day in question, then, is the Passion, which the disciples do not "see". The implications are significant: contrary to the assumption, common since Conzelmann, that Luke presents a wholly deferred eschatology, Lang shows that Christ's apocalypse begins at the cross.
The same issue also has a discussion of Kavin Rowe's World Upside Down, including Matthew Sleeman, John Barclay, and a response from Rowe himself.