In order of :
Saving diskspace
Keeping them up to date on various machines and OS's.
I replaced some Desktop files by a symlink to them on my NAS.
Mainly html,txt and m3u.
On the screen they kept their name and default icon fine!
But if I click on them the associated program doesn't launch any more.
If I open the menu and choose the same program in the "open with other application" option it works.