IIRC it largely depended on the age of the carriage. Some newer slam-door carriages had the door sensor and remotely operable lock, but most of the stock did no

IIRC it largely depended on the age of the carriage. Some newer slam-door carriages had the door sensor and remotely operable lock, but most of the stock did not and was of an age already that they were due for replacement so retro-fitting wasn't cost-effective. That subset which did have the mechanisms in place may not have been counted in what was decommissioned in 2005 & prior. I'm pretty sure I used slam doors later than 2005 too.