Concatenated Video Fails to Display

[djd]

vlc (for MS Windows) was used to cut Part1.ts, Part2.ts. Part3.ts and Part4.ts from
a 4Gb video file. The four parts can be played independently by vlc.
An attempt was made to merge the four files. Although a 2.1Gb file was created,
(roughly the combined size of the four files) vlc cannot play it.

The command line (described in various vlc posts) was:

vlc Part1.ts Part2.ts Part3.ts Part4.ts --sout "#gather:std{access=file,dst=Ep2S7.ts}" --sout-keep

The vlc version is 2.2.1

Is the command line correct?

[search53]

Why not just create and save a playlist of these videos, then tell VLC to play it?

[djd]

a) In desperation, I did just that, but missed a lot of understanding of the resulting
movie (refer to b. below).

b) I have a subtitle file for the concatenated result which would be hard to synchronise
with the playlist of four parts

c) I would like to be able to concatenate as well as cut - it is supposed to be a vlc ability.