I was using kayak to find the lowest fare between PHL-CLE and CLE-PHL. Often, I find that ZFV-EWR-CLE and CLE-EWR-ZFV from United comes up very discounted over EWR-CLE and CLE-EWR nonstops, and pretty low in general for PHL CLE and about $137 one-way. I was considering going with this option, as it might be better than Delta's change planes in ATL which UA is pricing close.

Does it work exactly the same like a connection flight? I assume not atleast with checking bags as it would be done at EWR.

Suppose, I was flying CLE-EWR-ZFV but that I didn't take the EWR-ZFV train segment. Would I have to take the EWR-ZFW train ride in order for UA to post miles to my FF account?

Does UA have it's check in system well in place at 30th Street Station that it knows if I have boarded the ZFV-EWR train ride? Suppose for example, I ended up getting a ride to EWR. Would UA cancel my ticket on EWR-CLE because I didn't use the train?

Any travel experiences using ZFV would be helpful.