[till]

Where is the benefit of this solution compared with the current setup? Currently the shell users of the website can edit the website files, as all shell users share the same userid. If the users have a different userid, you will have to setup separate home directories for the users and seprarate jailkit jails etc., this will prevent the users from accessing the website files as they will not be able to leave their jail.

For security reasons, the goal was that group write permissions are not required for a website. If we change that, a website that has mod_php enabled can be used to hack all other websites or if there is a hack e.g. in phpmyadmin, the hacker can take over all websites then.