Except that doesn't work sometimes on Gnome Terminal. I've never been able to pin down exactly what causes it to break, but I have some machines where I have to do the key combo to make the copy and paste work and it's really annoying. Also, annoying is if you highlight something, then hit ctrl-shift-v and it puts in the text from the other cut buffer.

But the GP might be referring to the fact that copy and paste with anything but straight text is an outright shitshow on X. Compare to the copy and paste facilities from even ancient MacOS 6 it's downright stone age.