Did I mention DOO?
No
Did I mention ticket prices falling?
No
Can a guard be all-seeing and see everything happening on board a trio of units making up a 12 car set?
No
Is DOO unsafe?
If it is, then better convert ALL DOO operations to having a guard on board to operate the doors, so all London Underground, Overground, South Eastern Metro, Southern Metro, Chiltern [south of Banbury], Great Western Turbos, Thameslink, Great Northern, Scotrail, Greater Anglia, C2C, and any others, as soon as possible to ban this outdated dangerous system of working. Actually better make that having at least 2 guards on board, one to do the doors & dispatch, the other to be in the passenger areas to be available to the travelling public