Originally Posted by
Whenderson
(3) One of the supposed bonuses is going through US immigration in Dublin not Chicago, but they only had one officer on for the non-US line so it took over an hour to get through. (They had 4 on for the US line). There were machines for ESTA holders, which would have meant we could use the US line in theory, but staff wouldn't let us use them. So all in all, there was as much faffing around in Dublin as there would have been in Chicago.
That doesn't match my own experience at all.
I've done that maybe 6 times, most recently a few days ago on a July Saturday that is supposed to be the busiest travel day of the year and went through in around 10 minutes tops. As there is no lounge beyond the checks I leave it to about 75 minutes prior to departure (that is also what the lounge staff recommend).
I think something that is often missed about pre-clearance is the fact that it allows tighter connections in the US because the MCT is much shorter. I can get to several Florida snd West Coast destinations far earlier than would be the case when the schedule factors in MCT ex my UK regional airport.