The docuмent, Fiducia Supplicans, like all modernist literature, conflates the two terms, "couples in irregular situations" and "same-sex couples." A man who marries a Mormon woman in the sacristy because she agrees to rear the children Catholic is an "irregular couple." The canon law commentary calls such arrangements "irregular marriages."
Two men are not a "couple" at all, because they cannot fulfill the necessary matter of the sacrament. To use the term "couple" with same-sex individuals is misleading. The television and Hollyweird refer to ɧoɱosɛҳųαƖs as couples, and it is only the modernist heretics who distort the original meaning of the term.
It is sort of like conflating "dirty water" and "motor oil" when referring to the sacrament of Baptism. One is valid and the other is ipso facto invalid. But to refer to both substances as "irregular" is confusing because the language implies that motor oil is valid matter for baptism.
This Cardinal Fernandez (the co-author Prefect, clearly a SWEETIE PIE), is just playing the same modernist game which we have been fed for the past fifty years.