[vdr] Question to --edit mode

[Gero]

Hello,

I tried the usage of vdr with the --edit parameter and the habbit of vdr looks 
a bit strange to me:

When i use only the --edit parameter, vdr will fail and the log claims, that 
the given recording is not found below the default video-dir 
(/var/lib/video.00).

When I use vdr with a video-dir not contained in the path of the recording, 
the same happens.

So to cut a recording, I need to use --edit='/path/to/recording' and -v path 
(with path being a part of '/path/to/recording') which I think is quite a bit 
of redundant.

What about the situation, where the recording is on a read-only mounted drive 
and the video-dir given by -v option is the path to a local writable 
directory? Is it really necessary, that source-recording and target-recording 
are on the same path?

Is it very expensive to support different write location than the read 
location?

kind regards

Gero