In that scenario, the rather foolish bride and groom would be engaging in a gravely illicit act and in all likelihood would be guilty of mortal sin. Their culpability could arguably even be greater as they would only have to wait mere moments to do all the kissing (and more) they want.
It was infallibly defined as an error. Whether it was heresy or mere error seems to be a complex theological question I am not qualified to answer, however, I admitted later the distinction and addressed it.
It was Pope Alexander VII in March of 1666.
While your criticism may have some weight, I believe I have shown more honesty than typical in internet discussions, and I am pretty sure I am the only one in this thread to provide citations of actual Church teaching in support of my position…
Wait I found one other poster who did so: hymin in response #7 also provided a citation of Church teaching but not necessarily on the topic at hand (passionate kissing being a mortal sin)