You may remember that Manfred Christl who is emerging as a kind of vigilante of incorrect chemical structure determinations had debunked a previous claim and shown it to be a manifestation of a 100 year old reaction. There he goes again about the structure of some alleged cyclic allenes. But this time accompanied by a firm rebuttal; it's not often that you see the strong word "incorrect" in a scientific publication.
Are strained amides, where delocalization of the nitrogen electron lone pairs is not possible, still amides? Hell, yes!
References: Manfred Christl, Bernd Engels (2009). Stable Five-Membered-Ring Allenes with Second-Row Elements Only: Not Allenes, But Zwitterions Angewandte Chemie International Edition, 48 (9), 1538-1539 DOI: 10.1002/anie.200803476
Vincent Lavallo, C. Adam Dyker, Bruno Donnadieu, Guy Bertrand (2009). Are Allenes with Zwitterionic Character Still Allenes? Of Course! Angewandte Chemie International Edition, 48 (9), 1540-1542 DOI: 10.1002/anie.200804909