Not sure if this has come up before, and hope its relevant, (I searched but didn't find anything and didn't want to start a new thread) but yesterday something weird happened at MIA, and I hope this is relevant to other readers of this thread.

Arrived on BA209 yesterday, and it was an E satellite gate. So the train thing - then we got shepherded through a very weird set of corridors I've never seen before. I have lived in Miami for 14 years and in and out of MIA at least once a month, so I know it inside out, but this was all new.
Having walked through a bunch of totally empty halls and corridors, we then arrived at a totally empty immigration room - with half a dozen GE kiosks off to the right, where US citizens were also directed, others to the left.
No one else was there. Only the BA flight. My other half asked his immigration officer what was going on (he doesn't have GE so in the mobile passport line) and he was told it was a new system being trialed at MIA, with separate immigration and customs areas for particular flights. After immigration we walked into a small luggage carousel area with only 2 carousels, and only the BA flight on the board - and the bags came off within 15 mins which is rather fast for MIA. Then a quick walk from that area - and we pop out by door 10 and 11 - I think from plane to car, with checked luggage it was about 20 mins.

Hopefully this will be a thing - because it was so quick and efficient, I was amazed.

Sorry if someone else has already posted the above - I don't know how new this system is, or if it is for every flight, so don't bank on it happening if you are flying through Miami any time soon, but if you do, it is way better than anything that has gone before.

A quick caveat for connectors, as I know this thread was about Intl to Dom connections, I didn't pay too much attention to where you have to go if you are connecting - I did see connecting flights signs, but thats about it - what happens after that, I'm not sure sorry. Hope this is helpful. Safe flying everyone!