Dynamic addition and removal of filesink to pipeline

[Stephan Boltzmann]

Hello everybody out there using GStreamer,

My program (written in C) is streaming/displaying video to the screen 
and writes it to a file at the same time.
I would like to write to a file based on a condition.
This can be achieved with 'dynamic pipelines' in GStreamer as far as I 
see.
There is an example of a dynamic pipeline in the official GStreamer 
documentation and I also found some code on GitHub 
(https://gist.github.com/crearo/1dc01b93b2b513e0000f183144c61b20), but I 
don't get the gist of it:
The functions `gst_bin_remove` and `gst_object_unref` are called with 
the tee element as an character there.
Is this the most elegant way to achive what I want to implement? 
Wouldn't it be more elegant to switch the filesink on and off 
dynamically?

Kind regards
Stephan